Endeavour Achieves Record Annual Discoveries With Addition of 3.0Moz of M&I and 0.9Moz of Inferred Resources

ENDEAVOUR ACHIEVES RECORD ANNUAL DISCOVERIES WITH ADDITION OF 3.0MOZ OFM&I AND 0.9MOZ OF INFERRED RESOURCES

HIGHLIGHTS:

• 3.0Moz of M&I resources discovered at a cost of $16/oz, exceeding the 2021 discovery target of 2.5Moz
• M&I resources for flagship Ity, Houndé and Sabodala-Massawa mines have increased respectively by 26%, 20% and 11%, excluding 2021 mine depletion, while resource updates for other assets are underway
• M&I resources for the Lafigué deposit, on the Fetekro property, have grown by18% to 2.9Moz and Inferred resources have grown by 309% to 270koz, justifying a larger 4.0Mtpa plant for the DFS rather than the 3.0Mtpa originally contemplated in the PFS
• Exploration efforts also delineated 0.9Moz of Inferred resources, mainly at the Ity mine, where follow-up drilling isplanned for 2022
• Results mark the successful completion of the previous 5-year discoverytarget of 10-15Moz of Indicated resources; on track to deliver the next 5-year discovery target of 15-20Moz of Indicated resources

London, 17January 2022 – Endeavour Mining plc (LSE:EDV, TSX:EDV, OTCQX:EDVMF) (“Endeavour” or the “Group” or the “Company”) is pleased to announce the discovery of 3.0 million ounces of Measured and Indicated (“M&I”) resources and 0.9 million ounces of Inferred resources across its flagship Ity, Houndé and Sabodala-Massawa mines as well as at its Lafigué deposit on the Fetekro property, as presented in Table 1 below.

Table 1: Summary of Mineral ResourcesAdded in 2021 (in koz)

Mineral Reserve Estimates follow the Canadian Institute of Mining, Metallurgy and Petroleum ("CIM") definitions standards for mineral resources and reserves and have been completed in accordance with the Standards of Disclosure for Mineral Projects as defined by National Instrument 43-101. Reported tonnage and grade figures have been rounded from raw estimates to reflect the relative accuracy of the estimate. Minor variations may occur during the addition of rounded numbers. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. Resources were constrained by MII Pit Shell and based on a cut-off grade of 0.5 g/t Au and $1,500/oz gold price. Further details are provided in the tables below and within the Technical Notes section of this press release.

Exploration and resource estimation activities were prioritised at the flagship mines and Fetekro for incorporation into the upcoming definitive feasibility study (“DFS”), which is due to be completed this quarter. Resource updates for all the other assets will be included in the annual year-end reserve and resource update, which is expected to be published along with the FY-2021 financial results in March 2022.

The strong results from the 2021 exploration programme have positioned Endeavour well to achieve its 5-year (2021-2025) discovery target of 15 to 20 million ounces of Indicated resources at a discovery cost of less than $25 per ounce, as previously announced on 30 September 2021 – for reference, click here to view the 5-Year Exploration Strategy presentation and click here to view the accompanying video presentation.

Sebastien de Montessus, President and CEO, said: “The significant discoveries we have made showcase the strong exploration potential within our portfolio and continue to confirm West Africa as one of the world’s top regions for gold discoveries. Our exploration programme continues to add significant value to the business, creating the potential to extend mine lives to well beyond 10 years whilefeedingour development pipeline.We are particularly pleased with the significantdiscoveries madeat our flagship mines,Ity, Houndé andSabodala-Massawa.

At our Ity mine, we have added over 1 million ounces of resources which is an extraordinary achievement. The West Flotouo deposit represents a significant discovery given its rich gradesabove 2 g/t Au, its size, and its location in close proximity to the plant. We will therefore aim to integrate the deposit within the mine plan as soon as possible. Looking ahead, work is continuing to convert the significant Inferred resources into Indicated status and to pursue our aggressive exploration programme.

At our Houndé mine, after locking-in more than10 years of strong production visibility through the recent discoveries of
Kari Pump and Kari Center, we are very pleased to have made yet another significant discovery with the Mambo depositand expect to be quickly integrate the higher-grade southern extensioninto the mine plan. Given the significant resources defined over recent years and its current long mine life,we will study the potential to bring forward production.

At our Sabadola-Massawa mine, which was acquired last year, we are pleased to have quickly increased the M&I resource base by 10% with the addition of more than 600,000 ounces. We are very excited to pursue our drilling campaign into 2022 as we continue to see potential to add resources, both by extending known deposits and initiating exploration on several identified targets.

At our Fetekro property, our continued exploration success at the Lafigué deposit, which now hosts approximately 3 million ounces of resources, means that itcan be considered an anchor deposit capable of supporting an Endeavour-sized project. Given today’s increase in Indicated resources to approximately 3 million ounces and the strong additional exploration potential, we have decided to increase the envisaged nameplate throughput capacity of the plant by 33% to 4Mtpa and look forward to publishing the results of the DFS later this quarter.

Given the exploration potential across our portfolio, we willcontinue to invest in exploration to further unlock value. I would like to congratulate our exploration team for achieving their best annual performance which positions us well to discover our 5-year target of 15-20 million ounces.”

Patrick Bouisset, Executive Vice President Exploration and Growth said: “The success of our 2021 exploration programme marks the completion of our first 5-Year exploration target, set in 2016. The immense effort and dedication from my team over the last 5 years has delivered over 10Moz of Indicated resource discoveries across our legacy portfolio, at a discovery cost below $25 per ounce, thereby achieving our ambitious target.

We are particularly proud to have significantly extended the lives of our Houndé and Ity mines, raising their status to flagship assets, as well as the discovery of the Lafiguédeposit on the Fetekro property which is now an Endeavoursize project.

Looking ahead, we believe that we have astrategic footholdin West Africa, which has grown into a leading global gold producing region, as we control some of the most prospective grounds andhave a highly experienced teamwith a proven explorationmethodology. We are excited to now focus on deliveringour new 5-year discovery target, which represents replacing twice the mine depletion over the period.”

ITY MINE DISCOVERIES

During 2021, over 72,000 meters of drilling was completed at Ity and as shown in Table 2 below, exploration efforts have delineated 975koz of Indicated resources representing a 26% increase over the 31 December 2020 M&I resource estimate, excluding 2021 mine depletion. At Ity, Indicated resources were discovered at a very low discovery cost of $11/oz. In addition, 571koz of Inferred resources were delineated and will be followed-up.

Table 2: Ity Mine Updated Mineral Resource Estimate

Updated Resource is current as at31 December 2020, as it excludes 2021 mine depletion. Mineral Resources and Reserve Estimates follow the Canadian Institute of Mining, Metallurgy and Petroleum ("CIM") definitions standards for mineral resources and reserves and have been completed in accordance with the Standards of Disclosure for Mineral Projects as defined by National Instrument 43-101. Reported tonnage and grade figures have been rounded from raw estimates to reflect the relative accuracy of the estimate. Minor variations may occur during the addition of rounded numbers. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. Resources were constrained by MII Pit Shell and based on a cut-off grade of 0.5 g/t Au and $1,500/oz gold price. Details for the Updated Resource are provided in the Technical Notes section of this press release. For details regarding the 31 December 2020 resources, please consult the press release dated 18 March 2021 at Endeavour.

Exploration focused on the junction between Walter and Bakatouo, the West Flotouo deposit, the Le Plaque deposit and its adjacent Yopleu-Legaleu target. The discoveries are detailed in Table 3 below. As shown in Figure 1, the resources that have been added are all within a short hauling distance to the Ity CIL plant.

Figure 1: Ity Map

Table 3: Ity Resource Additions

Updated Resource is current as at31 December 2020, as it excludes 2021 mine depletion. Mineral Resources and Reserve Estimates follow the Canadian Institute of Mining, Metallurgy and Petroleum ("CIM") definitions standards for mineral resources and reserves and have been completed in accordance with the Standards of Disclosure for Mineral Projects as defined by National Instrument 43-101. Reported tonnage and grade figures have been rounded from raw estimates to reflect the relative accuracy of the estimate. Minor variations may occur during the addition of rounded numbers. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. Resources were constrained by MII Pit Shell and based on a cut-off grade of 0.5 g/t Au and $1,500/oz gold price. Details for the Updated Resource are provided in the Technical Notes section of this press release. For details regarding the 31 December 2020 resources, please consult the press release dated 18 March 2021 at Endeavour.

Walter-Bakatouo: resource extension

• The 2021 drilling campaign confirmed that mineralisation is continuous between the Walter and Bakatouo deposits.
• The resource ore type is 71% fresh and the overall strip ratio is expected to remain low.
• The 2022 exploration programme will aim to increase the resource size further as the mineralisation remains open at depth.

West Flotouo: maiden resource

• The re-interpretation of structural and geological data with follow-up drilling led to the discovery of the West Flotouo deposit, which is located partially below the former Verse Ouest and TSF, in close proximity to the existing plant.
• The mineralisation has been identified over 0.8km in length and 0.3km in width. It remains open along strike to the southwest and northeast and at depth. The 2022 exploration programme has been designed to test the along strike and down dip extensions.
• The West Flotouo deposit will be integrated into the mine plan as soon as possible as it is a very attractive discovery due to its high grade, proximity to the plant, and resource ore type being 95% fresh material with high expected recovery rates.

Le Plaque: resource extension

• During the 2021 drilling campaign, an updated mineral resource was defined at Le Plaque, extending mineralisation towards Le Plaque SW and at depth at Delta Extension.
• The high grade Le Plaque deposit has been extended to the south towards Delta Extension and Le Plaque southwest. Resource ore type is 77% fresh and the strip ratio is expected to be in line with the previous Le Plaque resource, where mining began in late 2021.
• Mineralisation remains open to the southwest and at depth, with significant high-grade mineralisation identified outside of the current resource pit shell. At Delta Extension, the mineralisation continues at depth and further exploration will explore the underground resource potential.

Yopleu-Legaleu: maiden resource

• The promising early drilling results at Yopleu-Legaleu, located in the Le Plaque area east of Delta Extension were followed up on in the 2021 drilling campaign, resulting in a maiden Inferred resource.
• Mineralisation is 56% fresh ore and the strip ratio is expected to be significantly lower than that of Le Plaque.
• Mineralisation is open at depth and along strike and a second phase of drilling is planned as part of the 2022 exploration programme, with the aim of converting Inferred resources into Indicated resources and to increase the size of this satellite deposit.

HOUNDÉ MINE DISCOVERIES

• During 2021, over 70,000 meters of drilling was completed at Houndé. As shown in Table 4 below, recent exploration efforts have delineated 889koz of Indicated resources, representing a 20% increase over the 31 December 2020, M&I resource estimate, excluding 2021 mine depletion. At Houndé Indicated resources were discovered at the low discovery cost of $16/oz.

Table 4: Houndé Mine Updated Mineral Resource Estimate

Updated Resource is current as at31 December 2020, as it excludes 2021 mine depletion. Mineral Resources and Reserve Estimates follow the Canadian Institute of Mining, Metallurgy and Petroleum ("CIM") definitions standards for mineral resources and reserves and have been completed in accordance with the Standards of Disclosure for Mineral Projects as defined by National Instrument 43-101. Reported tonnage and grade figures have been rounded from raw estimates to reflect the relative accuracy of the estimate. Minor variations may occur during the addition of rounded numbers. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. Resources were constrained by MII Pit Shell and based on a cut-off grade of 0.5 g/t Au and $1,500/oz gold price. Details for the Updated Resource are provided in the Technical Notes section of this press release. For details regarding the 31 December 2020 resources, please consult the press release dated 18 March 2021 at Endeavour.

Exploration focussed on the Mambo target, where a maiden resource was delineated, the Kari Center-Gap-South area where the resource was extended, while limited work was done on the Vindaloo South target where an initial maiden resource was identified. The discoveries are detailed in Table 5 below. As shown in Figure 2, all the resources added are within trucking distance to the Houndé plant. Looking ahead, drilling higher-grade targets such as Sia Sianikoui and Dohoun are the next top priorities. 

Figure 2: Houndé Map

Table 5: Houndé Resource Additions

Mineral Resources and Reserve Estimates follow the Canadian Institute of Mining, Metallurgy and Petroleum ("CIM") definitions standards for mineral resources and reserves and have been completed in accordance with the Standards of Disclosure for Mineral Projects as defined by National Instrument 43-101. Reported tonnage and grade figures have been rounded from raw estimates to reflect the relative accuracy of the estimate. Minor variations may occur during the addition of rounded numbers. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. Resources were constrained by MII Pit Shell and based on a cut-off grade of 0.5 g/t Au and $1,500/oz gold price. Details for the Updated Resource are provided in the Technical Notes section of this press release. For details regarding the 31 December 2020 resources, please consult the press release dated 18 March 2021 at Endeavour.

Mambo: maiden resource

• Mambo is an attractive deposit as it is expected to have a low strip ratio, the resource contains approximately 40% oxide and transitional material, and there is the potential to selectively mine higher grade areas as a priority. Approximately a third of the resource, hosted in the mafic volcanics in the southwestern portion of the deposit, is higher grade, typically above 2g/t. For reference, based on a cut-off grade of 1.5 Au g/t within the $1,500 MII pit shell, the M&I resource totals 2.6 million tonnes at 2.1 Au g/t containing 172,000 ounces.
• The higher-grade portion of the Mambo deposit is expected to be integrated within the Houndé mine plan as a priority. In addition, given that the Mambo and Kari Center-Gap-South discoveries now represent 1.4Moz at over 1 g/t Au, Endeavour will assess the potential to bring forward lower-grade production by assessing the viability of adding a low-grade heap leach operation in addition to further de-bottlenecking Houndé’s plant.
• The mineralised trend at Mambo has been defined over 1,400 meters, and it remains open to the southwest (where the grade is higher), northeast, and at depth. The Mambo continuous ore zone is between 10-40 meters thick, with higher grade mineralisation concentrated at the contacts between the mafic volcanics and the granite, as shown in Figure 3 below. Further exploration work will continue to delineate the extent of the Mambo orebody along strike and down dip, within the southwestern portion of the deposit where grades are higher.

Figure 3: Mambo Plan Map

Kari Centre-Gap-South: resource extension

• During the 2021 drilling campaign, an updated mineral resource was defined from Kari Centre, Kari Gap and Kari South as drilling followed the continuity of the mineralised trend and successfully expanded the resources at each of these deposits.
• Mineralisation in the Kari area remains open at depth, north of Kari Center, and south of Kari South and the mineralised trend extends through all three deposits and beyond.
• The mineralisation, which is two thirds oxide and transitional, is expected to have a low strip ratio, it has strong lithological and structural control and there is the potential to selectively mine higher grade areas as a priority.
• Higher grade mineralisation is associated with brittle zones along structural controls, as shown in Figures 4 and 5 below. 

Figure 4: Kari Centre-Gap-South Plan Map

Figure 5: Kari Centre-Gap-South Cross Sections A and B

Vindaloo South: maiden resource

• During the 2021 drilling campaign, a maiden resource was defined at Vindaloo South, which is located only 3.5 kilomeetres south of the Houndé plant just outside the existing mining license.
• The Vindaloo South deposit covers an area of approximately 300 meters along strike with a width of approximately 100 meters and remains open at depth.
• Reconnaissance drilling has indicated that the mineralised trend continues towards the southern part of Vindaloo South.
• The resource is 98% oxide and transitional ore with an indicative strip ratio below the Houndé life of mine strip ratio.

SABODALA-MASSAWA MINE DISCOVERIES

During 2021, over 110,000 meters of drilling was completed at Sabodala-Massawa. As shown in Table 6 below, exploration efforts have delineated 591koz of Indicated resources representing a 11% increase over the 31 December 2020 M&I resource estimate, excluding 2021 mine depletion. At Sabodala-Massawa Indicated resources were discovered at the low discovery cost of $20/oz.

Table 6: Sabodala-Massawa Mine Updated Mineral Resource Estimate

Updated Resource is current as at31 December 2020, as it excludes 2021 mine depletion. Mineral Resources and Reserve Estimates follow the Canadian Institute of Mining, Metallurgy and Petroleum ("CIM") definitions standards for mineral resources and reserves and have been completed in accordance with the Standards of Disclosure for Mineral Projects as defined by National Instrument 43-101. Reported tonnage and grade figures have been rounded from raw estimates to reflect the relative accuracy of the estimate. Minor variations may occur during the addition of rounded numbers. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. Resources were constrained by MII Pit Shell and based on a cut-off grade of 0.5 g/t Au and $1,500/oz gold price. Details for the Updated Resource are provided in the Technical Notes section of this press release. For details regarding the 31 December 2020 resources, please consult the press release dated 18 March 2021 at Endeavour.

The exploration programme focussed on Massawa, Sofia, Delya, Tina and Samina on the Massawa permit area, with the discoveries detailed in Table 7 below. As shown in Figure 6, the exploration programme focussed on targets within trucking distance to the Sabodala mill.

Figure 6: Sabodala-Massawa map

Table 7: Sabodala-Massawa Resource Additions

Mineral Resources and Reserve Estimates follow the Canadian Institute of Mining, Metallurgy and Petroleum ("CIM") definitions standards for mineral resources and reserves and have been completed in accordance with the Standards of Disclosure for Mineral Projects as defined by National Instrument 43-101. Reported tonnage and grade figures have been rounded from raw estimates to reflect the relative accuracy of the estimate. Minor variations may occur during the addition of rounded numbers. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. Resources were constrained by MII Pit Shell and based on a cut-off grade of 0.5 g/t Au and $1,500/oz gold price. Details for the Updated Resource are provided in the Technical Notes section of this press release. For details regarding the 31 December 2020 resources, please consult the press release dated 18 March 2021 at Endeavour.

Massawa Central Zone: resource extension

• The 2021 drilling campaign, which was designed to better delineate the Southern continuity of the ore body, led to the successful extension of the main ore body.
• The Massawa Central Zone forms the southern part of the Massawa deposit and now occurs over a strike length of 900 meters. Mineralisation remains open to the south and there is scope to extend the main ore zone.

Massawa North Zone: resource extension

• The 2021 drilling campaign, which was designed to better characterise the mineralisation in the Massawa North Zone and test the extension of the main ore zone through step out drilling, successfully led to resource delineation.
• The Massawa North Zone occurs immediately north of the Massawa Central Zone deposit and now covers a strike length of 3,500 meters, follow up drilling will focus on delineating the extension of the main ore zone.

Sofia: resource extension

• During the 2021 drilling campaign, an updated mineral resource was defined based on drilling conducted at the Sofia North Extension.
• The drilling campaign successfully discovered a significant mineralised zone that extends 800 meters along strike and 150 meters wide, and remains open to the north towards the Matiba prospect. 

Tina: maiden Indicated resource

• The 2021 drilling campaign mainly targeted the North and East extensions of the known Tina deposit. Drilling results have allowed better delineation of the mineralised trend, which has been significantly extended to more than 800 meters around the central and footwall orezones.
• A low strip ratio is expected and the ore is predominantly refractory, fresh material, owing to the shallow weathering profile at the Tina deposit.
• In relation to mineralised extensions that were delineated at Tina, a new Northeast striking mineralised occurrence has been recognised, located approximately 300 meters to the Southeast of the Tina deposit. Further reconnaissance drilling will focus on delineating this new trend in 2022.

Samina: maiden resource

• Located approximately 23km southeast of the Sabodala mill, mineralisation at Samina is made up of fresh and transitional ore that is largely non-refractory. During the 2021 drilling campaign, exploration efforts were focussed on systematic infill and extension to the Southwest and East to define the updated mineral resource.
• The mineralised strike length has now been extended to more than 1,100 meters and mineralisation remains open to the northeast and southwest as well as at depth.

Delya: resource model update

• An updated mineral resource was defined at Delya based on updated resource modelling work.
• The mineralised zone at Delya is up to 10 meters thick, with local zones of higher grades.
• The mineralisation is generally associated with strongly disseminated fine arsenopyrite and pyrite. Gold is largely refractory in nature.

LAFIGUÉ DEPOSIT - FETEKRO PROPERTY

Endeavour received the mining permit for the Lafigué deposit on 22 September 2021, which will be operated by the newly created Société des Mines de Lafigué entity, which is 80% owned by Endeavour, with the State and SODEMI each owning a 10% stake.

Since the last resource update on 18 August 2020, more than 66,000 meters of drilling have been completed on the Lafigué deposit, in addition to 4,920 meters drilled to initiate the exploration of nearby targets.

The recent drilling programme over the Lafigué deposit comprised 246 reverse circulation (“RC”) holes totalling 43,484 meters and 70 combined RC/DD holes totalling 22,606 meters. The drilling campaign was designed to further extend the economic mineralisation at the south end of Lafigué North, to upgrade existing Inferred resources to Indicated status and to drill geotechnical holes to support the ongoing DFS.

As shown in the Figures 7 to 9, drilling was mainly focussed in the area located between the Lafigué Center and Lafigué North deposits. The results of this drilling activity successfully demonstrated the overall continuity of the mineralised system with the occurrence of shallow, subparallel, and stacked mineralised lenses that were previously located outside of the 2020 resources pit shell. In addition, a minor part of the exploration programme focused on converting some of the remaining Inferred resources into Indicated resources at the Lafigué North deposit.

Figure 7: Lafigué Geological Interpretation and Selected Best Intercepts Per Area

Figure 8: Section A – A’ : Between Lafigué Center and Lafigué North  

Figure 9: Section B – B’ : Lafigué North

As shown in the table below, following the successful drilling campaign, the Indicated resource estimate has grown by 445koz to 2.9Moz. The upcoming DFS will be based on this updated November 30 2021 resource estimate, which was prepared by SRK Consulting (UK) Ltd in order to provide an independent external mineral resource estimate, whereas the previous estimate was internally prepared by Endeavour. Given the difference in geological modelling approach, the updated Indicated resource grade now better reflects the Probable reserve grade as estimated by SRK Consulting (UK) Ltd during the preparation of the pre-feasibility study published last year.

Table 8: LafiguéUpdated Mineral Resource Estimate

Mineral Reserve Estimates follow the Canadian Institute of Mining, Metallurgy and Petroleum ("CIM") definitions standards for mineral resources and reserves and have been completed in accordance with the Standards of Disclosure for Mineral Projects as defined by National Instrument 43-101. Reported tonnage and grade figures have been rounded from raw estimates to reflect the relative accuracy of the estimate. Minor variations may occur during the addition of rounded numbers. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. Resources were constrained by MII Pit Shell and based on a cut-off of 0.5 g/t Au. Endeavour’s stake in the Fetekro property is not considered to be material to the issuer and therefore Endeavour does not expect to issue a technical report following this press release.

A sensitivity analysis performed at gold prices between $1,300/oz and $1,700/oz demonstrates the robustness of the Lafigué Indicated resource due to its high-grade mineralisation, as shown in Table 9 below.

Table 9: Lafigué 30 November 2021 Mineral Resource Estimate

No Measured resources have been estimated. Mineral Resource estimates follow the Canadian Institute of Mining, Metallurgy and Petroleum ("CIM") definitions standards for mineral resources and reserves and have been completed in accordance with the Standards of Disclosure for Mineral Projects as defined by National Instrument 43-101. Reported tonnage and grade figures have been rounded from raw estimates to reflect the relative accuracy of the estimate. Minor variations may occur during the addition of rounded numbers. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. Resources were constrained by MII $1,500/oz
Pit Shell and for sensitivity purpose by MII $1,300/oz and $1700/oz pit shells and based on a cut-off of 0.5 g/t Au.

Given the increase in Indicated resources and the strong additional exploration potential, Endeavour has decided to increase the envisaged nameplate throughput capacity of the plant by 33% to 4Mtpa in the DFS, which is expected to be published in late Q1-2022.

In the near-term, the Lafigué deposit remains the priority at Fetekro, while the longer-term focus is on delineating several identified targets on the property. Due to the high priority given to Lafigué, very little exploration drilling has been done on these targets to date. Over the last 12 months, approximately 4,920 meters of reconnaissance drilling were only conducted on Targets 1, 2, 9 and 11. Best selected intercepts, including Western Area, Target 3 and 4 are shown in the Figure 10 below. Further exploration on these and other targets will be pursued in 2022 and beyond.  

Figure 10: Properties Plan Map with Exploration Targets

TECHNICAL NOTES

ITY MINE

West Flotouo geology and resource modelling

The West Flotouo orebody sits within the Ity mining complex. The geology consists of a NW dipping volcano sedimentary sequence (meta-conglomerate to the SE and detritic metasediments interbedded with amphibolite layers to the NW) intruded by a felsic dyke (granodiorite) dipping to the NW. A diorite intrusive also occurs to the NE of the prospect. All lithological units have been affected by shearing. The mineralisation is associated with a series of stacked brittle ductile NE-SW trending shear zones dipping 30°-50° to the NW.

Several minor drilling campaigns cumulating 4,257 meters (m) of reverse circulation (RC), diamond (DD) and Air Core Drilling (AC) were carried out between 2013 and 2017. In 2020, an intensive drilling program aiming to assess the potential of the prospect was undertaken. Since then, the drilling program over the West Flotouo deposit comprised 102 reverse RC holes totalling approximately 17,500m, 31 DD holes totalling approximately 6,800m, and 24 combined RC and DD holes totalling approximately 6,000m.

The statistical analysis, geological modelling and resource estimation were prepared by Endeavour resource staff. The Qualified Person as defined by NI 43-101, that is taking responsibility for the statistical analysis, geological modelling and resource estimation is
Kevin Harris, CPG, Vice President Resources for Endeavour.

The West Flotouo Mineral Resource model was developed in Seequent’s Leapfrog Geo and Geovia’s Surpac software. The database used to generate the Mineral Resource comprised some 170 drillholes, with a total drilling meterage of 31,850m. All drilling was supported by industry standard quality assurance and quality control systems, with quality control sampling comprising blanks, coarse blanks, certified reference materials, and field and pulp duplicates. Endeavour Mining Resource and Database departments have reviewed the QAQC data available and considers the assay data to be suitable for use in the subsequent Mineral Resource estimate.

Twenty mineralisation domains were modelled using Leapfrog Geo vein modelling tools and cross section interpretations. The gold assays from the drill holes were composited to 1.0m intervals. Capping varied depending on the mineralised domain, between 10 g/t Au and 25 g/t Au. Spatial analysis of the gold distribution indicated good continuity of the grades along strike and down dip within the mineralised zones. Variogram ranges in the direction of maximum continuity were between 50m and 65m.

Density measurements from 990 samples and covering each of the lithologies, were averaged based on the material type (and lithology, in the case of fresh material). Average density values were applied to the associated portions of the block model as outlined below:

• Laterite/Overburden: 1.30 g/cm³
• Saprolite: 1.40 g/cm³
• Saprock: 2.40 g/cm³
• Fresh: Sediments 2.84 g/cm³; Granodiorite 2.80 g/cm³; Skarn 3.00 g/cm³; Diorite 2.90 g/cm³;

Gold grades were estimated using Ordinary Kriging using two passes of calculation to define the higher confidence areas and extend the grade to the interpreted mineralised zone extents.

The grade estimation was validated with visual and statistical analysis, and comparison with the drilling data on sections with swath plots comparing the block grades with the composites.

Endeavour considers that the quality and spatial distribution of the data used, the geological continuity of the mineralisation and the quality of the estimated block model for West Flotouo deposit is sufficient for the reporting of Indicated and Inferred Mineral Resources, in accordance with the CIM Definition Standards. Indicated Mineral Resources have been defined by drill hole data with a 45m range, where there is a reasonable level of confidence in geological and grade continuity. The inferred resource is defined to the remaining blocks within the mineralised zone within a 75m range, where the controls on mineralisation are less well understood, or the continuity is much reduced. The classification within each mineralised domain was smoothed to provide continuity of the classification.

Mineral Resources are reported within a $1,500 optimised pit shell using cut-off of grades of 0.5 g/t. Basic pit optimization parameters used are defined below:

• Mining cost: 2.75 (US$/t) Oxide; 3.00 (US$/t) Transition; 3.25 (US$/t) Fresh
• Processing cost: 15.85 (US$/t) Oxide; 16.79 (US$/t) Transition; 17.61 (US$/t) Fresh
• Selling cost: 70 (US$/oz Au)
• Mining recovery: 95%
• Mining dilution: 10%
• Processing recovery: 92% Oxide; 90% Transition/Fresh
• Average slope angles: 40°
• Gold Price: 1500 US$/oz

Walter-Bakatouogeology and resource modelling

The 2020-2021 drilling programme over the Walter-Bakatouo deposit comprised 86 RC holes totalling approximately 13,400m, 5 DD holes totalling approximately 1,000m, and 11 combined RC/DD holes totalling approximately 2,700m to test down dip mineralization continuity to NE and SW.

Drilling assay results have returned significant intercepts at high Au grades, including 17.9m at 4.03g/t Au in hole WA21-028, with mineralised envelops still open along strike to the NE and SW, as well as at depth.

Thanks to the successful drilling campaign, the Indicated resource estimate has grown demonstrating once again the gold endowment of the Ity Area.

Mineralization is associated with:

• pyrite, chalcopyrite, magnetite and local bornite or covellite, hosted in endoskarn-exoskarn.
• pyrite and chalcopyrite hosted in sheared diorite and volcano-sediment.

The statistical analysis, geological modelling and resource estimation were prepared by Endeavour resource staff. The Qualified Person, as defined by NI 43-101, that is taking responsibility for the statistical analysis, geological modelling and resource estimation is Mr Kevin Harris, CPG, VicePresident Resources for Endeavour.

The Walter-Bakatouo Mineral Resource model was developed in Seequent’s Leapfrog Geo and Geovia’s Surpac software. The database used to generate the Mineral Resources comprised some 614 drillholes, with a total drilling meterage of 68,564m. All drilling was supported by industry standard quality assurance and quality control systems, with quality control sampling comprising blanks, coarse blanks, certified reference materials, and field and pulp duplicates. Endeavour Mining Resource and Database departments have reviewed the QAQC data available and considers the assay data to be suitable for use in the subsequent Mineral Resource estimate.

Forty-four mineralisation domains were modelled using Leapfrog Geo vein modelling tools and cross section interpretations. The gold assays from the drill holes were composited to 1.0m intervals. Capping varied depending on the mineralised domain between 5 and 25 g/t. Spatial analysis of the gold distribution has been performed using GEOVIA Surpac software, indicated good continuity of the grades along strike and down dip within the mineralised zones. Variogram ranges in the direction of maximum continuity were between 30m and 60m with a 45m average.

Density measurements from 4,101 samples and covering each of the lithologies, were averaged based on the material type (and lithology, in the case of fresh material). Average density values were applied to the associated portions of the block model as outlined below:

• Laterite/Overburden: 1.50 g/cm³
• Saprolite: 1.40 g/cm³
• Saprock: Sediments/Carbonates 2.80 g/cm³; Granodiorite 2.70 g/cm³; Skarn 2.90 g/cm³; Diorite 2.90 g/cm³
• Fresh: Sediments/Carbonates 2.84 g/cm³; Granodiorite 2.80 g/cm³; Skarn 3.00 g/cm³; Diorite 2.90 g/cm³

Gold grades were estimated using Ordinary Kriging using two passes to define the higher confidence areas and extend the grade to the interpreted mineralised zone extents.

The grade estimation was validated with visual and statistical analysis, and comparison with the drilling data on sections with swath plots comparing the block grades with the composites.

Endeavour considers that the quality and spatial distribution of the data used, the geological continuity of the mineralisation and the quality of the estimated block model for Walter-Bakatouo deposit is sufficient for the reporting of Indicated and Inferred Mineral Resources, in accordance with the CIM Definition Standards. Indicated Mineral Resources have been defined by drill hole data with a 40m range, where there is a reasonable level of confidence in geological and grade continuity. The inferred resource is defined to the remaining blocks within the mineralised zone within a 70m range, where the controls on mineralisation are less well understood, or the continuity is much reduced. The classification within each mineralised domain was smoothed to provide continuity of the classification.

Mineral Resources are reported within a $1,500 optimised pit shell using cut-off of grades of 0.5 g/t Au. Basic pit optimization parameters used are defined below:

• Mining cost: 2.75 (US$/t) Oxide; 3.00 (US$/t) Transition; 3.25 (US$/t) Fresh
• Processing cost: 15.85 (US$/t) Oxide; 16.79 (US$/t) Transition; 17.61 (US$/t) Fresh
• Selling cost: 70 (US$/oz Au)
• Mining recovery: 95%
• Mining dilution: 10%
• Processing recovery: 94% Oxide; 90% Transition/Fresh
• Average slope angles: 40°
• Gold Price: 1500 US$/oz

Yopleau-Legaleugeology and resource modelling

Another promising mineralised structure, Yopleu-Legaleu, was confirmed 1km east of the Le Plaque orebody. The mineralized bodies occur in the granodiorite in the form of parallel lenses in echelon following an overall direction of N015° to N020°dipping 55° to 65°W.

The statistical analysis, geological modelling and resource estimation were prepared by Endeavour resource staff. The Qualified Person, as defined by NI 43-101, that is taking responsibility for the statistical analysis, geological modelling and resource estimation is
Kevin Harris, CPG, Vice President Resources for Endeavour.

The Yopleu Mineral Resource model was developed in Seequent’s Leapfrog Geo software and Geovia’s Surpac software. The database used to generate the Mineral Resources comprised some 272 drillholes, with a total of 18,153m drilled. All drilling was supported by industry standard quality assurance and quality control systems, with quality control sampling comprising blanks, coarse blanks, certified reference materials, and field and pulp duplicates. The QAQC data was reviewed and considered the assay data to be suitable for use in the subsequent Mineral Resource estimate.

Ten mineralisation domains were modelled from interpreted cross sections. The gold assays from the drill holes were composited to 1.0m intervals. Capping varied depending on the mineralised domain, between no cap to 10g/t. Spatial analysis of the gold distribution within the mineralised zone indicated good continuity of the grades along strike and down dip within the mineralised zones. Variogram ranges in the direction of maximum continuity were 50m.

Density measurements from 191 samples from the core drillholes and covering each of the lithologies, were averaged based on the weathering zone. Average density values were applied to the associated portions of the block model as outlined below:

• Laterite: 1.55 g/cm³
• Saprolite: 1.50 g/cm³
• Saprock: 2.40 g/cm³
• Fresh: 2.80 g/cm³

Gold grades were estimated using an Inverse Distance Squared (“IDW2”) for the modelled mineralisation. The grade was estimated in multiple passes to define the higher confidence areas and extend the grade to the interpreted mineralised zone extents.

The grade estimation was validated with visual and statistical analysis, and comparison with the drilling data on sections with swath plots comparing the block grades with the composites.

Endeavour considers that the quality and spatial distribution of the data used, the geological continuity of the mineralisation and the quality of the estimated block model for Le Plaque deposit is sufficient for the reporting of Inferred Mineral Resources, in accordance with the CIM Definition Standards. Inferred Mineral Resources have typically been defined in areas with a drillhole spacing of 50 to 75m.

Mineral Resources are reported within a $1,500 optimised pit shell using cut-off of grades of 0.5 g/t. Basic pit optimization parameters used are defined below:

• Base mining cost: 2.67 (US$/t)
• Oxide mining cost (including haulage): 3.20 (US$/t)
• Transition mining cost (including haulage): 3.74 (US$/t)
• Fresh mining cost (including haulage): 4.01 (US$/t)
• Processing cost + G&A: Oxide 15.85 (US$/t); Transition: 16.79 (US$/t); Fresh: 17.61 (US$/t)
• Selling cost: 70 (US$/oz Au)
• Mining recovery: 95%
• Processing recovery: Oxide 94.6%; Transition 93.2%; Fresh 81%
• Average slope angles: 40°

Le Plaque geology and resource modelling

Mineralization is associated with narrow ductile and brittle-ductile shears with silica-sericite alteration, quartz veining and sulphides (Py, +/-Sp-Cpy-Gn-Pyr), mostly within a granodiorite intrusive.

A drilling program was undertaken to follow up on mineralisation extensions to the 30 June 2021 resource. Drilling confirmed the down-dip extensions of the mineralisation, it also revealed new shallow mineralised corridors to the SE of Delta extension and at Le Plaque SW. Both areas will be followed up in 2022. Since the maiden mineral resource, cumulative drilling at Le Plaque totals approximately 12,700m of which 7,200m was RC drilling and 5,500m was DD.

The statistical analysis, geological modelling and resource estimation were prepared by Endeavour resource staff. The Qualified Person, as defined by NI 43-101, that is taking responsibility for the statistical analysis, geological modelling and resource estimation is
Kevin Harris, CPG, Vice President Resources for Endeavour.

The Le Plaque Mineral Resource model was developed in Seequent’s Leapfrog Geo software and Geovia’s Surpac software. The database used to generate the Mineral Resources comprised some 1,399 drillholes, with a total of 144,584m drilled. All drilling was supported by industry standard quality assurance and quality control systems, with quality control sampling comprising blanks, coarse blanks, certified reference materials, and field and pulp duplicates. The QAQC data was reviewed and considered the assay data to be suitable for use in the subsequent Mineral Resource estimate.

Sixty-four mineralisation domains were modelled from interpreted cross sections. The gold assays from the drill holes were composited to 1.0m intervals. Capping varied depending on the mineralised domain, between no cap and 40g/t. Spatial analysis of the gold distribution within the mineralised zone indicated good continuity of the grades along strike and down dip within the mineralised zones. Variogram ranges in the direction of maximum continuity were between 45m and 65m.

Density measurements from 5,069 samples from the core drillholes and covering each of the lithologies, were averaged based on the weathering zone. Average density values were applied to the associated portions of the block model as outlined below:

• Laterite: 1.55 g/cm³
• Saprolite: 1.50 g/cm³
• Saprock: 2.40 g/cm³
• Fresh: 2.80 g/cm³

Gold grades were estimated using Ordinary Kriging for the majority of the modelled mineralisation. Where it was not possible to define a well-structured variogram for the smallest domains with low sample support, an Inverse Distance Squared (“IDW2”) estimator was used. The grade was estimated in multiple passes to define the higher confidence areas and extend the grade to the interpreted mineralised zone extents.

The grade estimation was validated with visual and statistical analysis, and comparison with the drilling data on sections with swath plots comparing the block grades with the composites.

Endeavour considers that the quality and spatial distribution of the data used, the geological continuity of the mineralisation and the quality of the estimated block model for Le Plaque deposit is sufficient for the reporting of Indicated and Inferred Mineral Resources, in accordance with the CIM Definition Standards. Indicated Mineral Resources have typically been defined in areas with a drillhole spacing of 25m along sections, and 25m between sections, where there is a reasonable level of confidence in geological and grade continuity. Inferred Mineral Resources have typically been defined in areas with a drillhole spacing of 50 to 75 m, and where the controls on mineralisation are less well understood, or the continuity is much reduced.

Mineral Resources are reported within a $1,500 optimised pit shell using cut-off of grades of 0.5 g/t. Basic pit optimization parameters used are defined below:

• Base mining cost: 2.67 (US$/t)
• Oxide mining cost (including haulage): 3.20 (US$/t)
• Transition mining cost (including haulage): 3.74 (US$/t)
• Fresh mining cost (including haulage): 4.01 (US$/t)
• Processing cost + G&A: Oxide 15.85 (US$/t); Transition: 16.79 (US$/t); Fresh: 17.61 (US$/t)
• Selling cost: 70 (US$/oz Au)
• Mining recovery: 95%
• Processing recovery: Oxide 94.6%; Transition 93.2%; Fresh 81%
• Average slope angles: 40⁰

HOUNDÉ MINE

Mambo geology and resource modelling

Mambo is located 12km north of the Houndé plant, the geology is composed of intermediate to mafic volcanics that have been intruded by an elongated granite body that trends NE-SW. Locally sericite and carbonate alteration and tectonic breccias and veining are present within the orezone. Sulphides, mostly pyrite, are also present as disseminations through the rock. At Mambo, laterite cover is approximately 20m thick, below which saprolite varies in thickness between 10m to 50m. Ore zones are continuous through saprolite and fresh rock and are dipping towards the NW at 25 to 40 degrees.

Mineralisation is approximately 10 - 40m thick, with higher grade material mainly concentrated at the contact between mafic volcanics and the granite, or in the altered mafic volcanics.

The mineralisation is very continuous and intercepts thicken within the granite body to between 30 - 40m. Further exploration work will continue to delineate the extent of the Mambo orebody along strike and down dip.

The statistical analysis, geological modelling and resource estimation were prepared by Helen Oliver FGS CGeol, Group Resource Geologist at Endeavour who is a Qualified Person as defined by NI 43-101.

The Mambo Mineral Resource model was developed in Geovia’s Surpac software. The database used to generate the Mineral Resource was comprised of 361 drillholes, with a total drilling meterage of 41,484 m. All of the drill holes, with the exception of two, were drilled in 2020 and 2021. Drilling was supported by industry standard quality assurance and quality control (QAQC) systems, with quality control sampling comprising blanks, coarse blanks, certified reference materials, and field and pulp duplicates. Endeavour has reviewed the QAQC data available and considers the assay data to be suitable for use in the subsequent Mineral Resource Estimate (MRE).

Mineralised zones were delineated on 40m sections at a threshold of 0.4 Au g/t with a minimum of three samples, equivalent to 2.5m vertical thickness. Extrapolation down- or up-dip and along strike was generally limited to 20m. Fourteen mineralised zones composed of 23 lenses were identified.

The gold assays were either not capped or capped at 5 Au g/t Au or 10 Au g/t depending on mineralised zone and composited to one metre down-the-hole intervals.

Spatial analysis of the gold distribution within the larger mineralised zones indicated good continuity of the grades along strike and down dip. Variogram ranges in the direction of maximum continuity were between 65m and 125m, typically about 85m.

Some 944 density measurements from 25 drill holes covering each weathering type (and lithology for fresh rock) were averaged. Average density values were applied to the block model, as outlined below:

• Laterite: 2.00 g/cm³
• Saprolite: 1.77 g/cm³
• Saprock: 2.34 g/cm³
• Fresh Rock: 2.76 g/cm³ (limited lithological variation, hence average value used)

Gold grades were estimated using Ordinary Kriging. The grade was estimated in multiple passes to define the higher confidence areas and extend the grade into areas with less sample coverage. The larger Mambo mineralised zones show a change in strike orientation and therefore dynamic anisotropy was used.

The grade estimation was validated by an Inverse Distance Squared (“IDW2”) estimate, by visual and statistical analysis, and swath plots comparing the block grades with the composites.

Endeavour considers that the quality and spatial distribution of the data used, the geological continuity of the mineralisation and the quality of the estimated block model for the Mambo deposit is sufficient for the reporting of Indicated and Inferred Mineral Resources in accordance with the CIM Definition Standards. Indicated Mineral Resources were typically defined in areas with a drillhole spacing of 40m along sections where there is a reasonable level of confidence in geological and grade continuity. Inferred Mineral Resources were typically defined in areas with a drillhole spacing of 80m, and where the controls on mineralisation are less well understood, or the continuity is much reduced.

The Mambo deposit has not been subjected to artisanal workings and therefore the MRE has not been depleted.

Mineral Resources are reported within a $1,500 optimised pit shell using a cut-off grade of 0.5 Au g/t. Technical and economic assumptions were made by Endeavour for mining factors (mining and selling costs, mining recovery and dilution, pit slope angles) and processing factors (gold recovery, processing costs) which were used for optimisation as summarised below:

• Base Mining cost: 2.00 (US$/t)
• Mining & Haulage cost: Oxide: 3.60 (US$/t); Transition: 4.60 (US$/t); Fresh: 4.80 (US$/t)
• Processing and G&A cost: Oxide: 14.00 (US$/t); Transition: 15.00 (US$/t); Fresh: 18.00 (US$/t)
• Selling cost: 80.00 (US$/oz Au)
• Mining recovery: 95%
• Mining dilution: 0%
• Processing recovery: 90%
• Slope angles: 40°

Kari Centre-Gap-South geology and resource modelling

Kari Centre-Gap-South is on a mineralised trend southwest of Kari Pump, located around 10km West of the Houndé plant. The geology is composed of interbedded mafic volcanic and volcano-sedimentary rocks. Sericite-albite alteration is observed within and around the mineralised envelope. Sulphides are present, with disseminated pyrite being the most dominant.

The mineralisation has strong lithological and structural control and is typically located along lithological boundaries between the volcanic and volcano-sedimentary units, these boundaries are also exploited by alteration. The mineralization is associated with quartz veins, sericite-albite alteration and finely disseminated pyrite. Higher grade mineralisation is also associated with brittle zones along structural controls. The Kari Centre structure is continuous and strikes towards the northeast, dipping at fifty degrees to the northwest.

At Kari Centre and Kari Gap laterite up to 25m thick is underlain by Saprolite up to 100 meters thick, while at Kari South the weathering profile is thinner, with laterite generally less than 15m thick and Saprolite less than 60m thick.

Mineralisation in the Kari area remains open at depth, north of Kari Center, and south of Kari South.

The statistical analysis, geological modelling and resource estimation were prepared by Helen Oliver FGS CGeol, Group Resource Geologist at Endeavour who is a Qualified Person as defined by NI 43-101.

The Kari Centre-Gap-South (KCGS) Mineral Resource model was developed in Geovia’s Surpac software. The database used to generate the Mineral Resource was comprised of 2,041 drill holes, with a total drilling meterage of 201,781 m. All drilling was supported by industry standard quality assurance and quality control (QAQC) systems, with quality control sampling comprising blanks, coarse blanks, certified reference materials, and field and pulp duplicates. Endeavour has reviewed the QAQC data available and considers the assay data to be suitable for use in the subsequent Mineral Resource Estimate (MRE).

Mineralised zones were delineated on 40m sections at a threshold of 0.3 Au g/t with a minimum of two samples, equivalent to 1.25m vertical thickness. Extrapolation down- or up-dip and along strike was generally limited to 20m. 82 mineralised zones were identified.

The gold assays were either not capped or capped at 5 Au g/t Au, 10 Au g/t or 25 Au g/t depending on mineralised zone and composited to one metre down-the-hole intervals.

Spatial analysis of the gold distribution within the mineralised domains in KCG indicated moderate continuity of the grades along strike and down dip. Variogram ranges in the direction of maximum continuity were typically between 50m and 80m. Variography was not undertaken in KS due to the small nature of the mineralised zones.

Some 4,081 density measurements covering each weathering type (and lithology for fresh rock) were averaged. Average density values were applied to the block model, as outlined below:

• Laterite: 2.00 g/cm³
• Saprolite: 1.80 g/cm³
• Saprock: 2.23 g/cm³
• Fresh Rock: 2.75 g/cm³ (limited lithological variation, hence average value used)

Gold grades were estimated using Ordinary Kriging (OK) in KCG and Inverse Distance Squared (ID2) in KS. The grade was estimated in multiple passes to define the higher confidence areas and extend the grade into areas with less sample coverage. The larger mineralised zones show a change in strike orientation and therefore dynamic anisotropy was used.

The OK grade estimation was validated by an Inverse Distance Squared estimate (“IDW2”). The OK and ID2 estimates were validated by visual and statistical analysis, and swath plots comparing the block grades with the composites.

Endeavour considers that the quality and spatial distribution of the data used, the geological continuity of the mineralisation and the quality of the estimated block model for the KCGS deposit is sufficient for the reporting of Indicated and Inferred Mineral Resources in accordance with the CIM Definition Standards. Indicated Mineral Resources were typically defined in areas filled by the first estimation pass (five samples from a minimum of three holes within 50m) where there is a reasonable level of confidence in geological and grade continuity. Inferred Mineral Resources were typically defined in areas filled by the second (and possibly the third) estimation pass (three samples from a minimum of two holes within 100m or 150m), and where the controls on mineralisation are less well understood or the continuity is much reduced.

The KCGS deposit has not been subjected to significant artisanal/orpaillage workings and therefore the MRE has not been depleted.

Mineral Resources are reported within a $1,500 optimised pit shell using a cut-off grade of 0.5 Au g/t. Technical and economic assumptions were made by Endeavour for mining factors (mining and selling costs, mining recovery and dilution, pit slope angles) and processing factors (gold recovery, processing costs) which were used for optimisation as summarised below:

• Base Mining cost: 2.00 (US$/t)
• Mining & Haulage cost: Oxide: 3.60 (US$/t); Transition: 4.60 (US$/t); Fresh: 4.80 (US$/t)
• Processing and G&A cost: Oxide: 14.00 (US$/t); Transition: 15.00 (US$/t); Fresh: 18.00 (US$/t)
• Selling cost: 80.00 (US$/oz Au)
• Mining recovery: 95%
• Mining dilution: 0%
• Processing recovery: Oxide: 95%; Transition: 90%; Fresh 85%
• Slope angles: 40°

Vindaloo South geology and resource modelling

Vindaloo South is located approximately 1.25km South of Vindaloo Main Pit, along the Vindaloo Main mineralised trend.

The laterite thickness is up to 15m and covers most of the area. Saprolite thickness varies between 5 to 40m (saprolite is thicker on the mineralized zone).

Vindaloo South deposit stratigraphy correlates to a package that occupies the hangingwall sequence at the Vindaloo Main pit. The sequence, from west to east, is composed of volcanoclastites with lapilli fragments, followed by sediments, which are sometimes graphitic, and is intruded by younger dioritic intrusive dykes.

The mineralization is hosted by a sub-vertical, generally NNE-SSW trending structure. Higher grade zones within the structure are interpreted to plunge moderately towards the south, possibly reflecting boudinage development as noted at the Vindaloo deposit. Volcanoclastite host rock associated with the mineralisation is moderately sericite altered, with quartz veining and local silicification. Gold appears to be associated with pyrite, which occurs as disseminated grains and minor veinlets. Minor amounts of mineralisation are also associated with younger dioritic intrusive dykes which occur in the southern part of the area.

The statistical analysis, geological modelling and resource estimation were prepared by Helen Oliver FGS CGeol, Group Resource Geologist at Endeavour who is a Qualified Person as defined by NI 43-101.

The Vindaloo South Mineral Resource model was developed in Geovia’s Surpac software. The database used to generate the Mineral Resource was comprised of 141 drillholes, with a total drilling meterage of 12,546m; the majority of the drill holes were drilled in 2021. Drilling was supported by industry standard quality assurance and quality control (QAQC) systems, with quality control sampling comprising blanks, coarse blanks, certified reference materials, and field and pulp duplicates. Endeavour has reviewed the QAQC data available and considers the assay data to be suitable for use in the subsequent Mineral Resource Estimate (MRE).

Mineralised zones were delineated on 40m sections at a threshold of 0.3 Au g/t with a minimum of three samples, equivalent to 2.5m vertical thickness. Extrapolation down- or up-dip and along strike was generally limited to 20m. Two mineralised zones were identified.

The gold assays were capped at 10 Au g/t and composited to one metre down-the-hole intervals.

Assumed density values were taken from the Vindaloo-Madras MRE and applied to the block model, as outlined below:

• Laterite: 1.8 g/cm³
• Saprolite: 1.9 g/cm³
• Saprock: 2.3 g/cm³
• Fresh Rock: 2.7 g/cm³

Gold grades were estimated using Inverse Distance Squared (”IDW2”)). The grade was estimated in two passes to define the higher confidence areas and extend the grade into areas with less sample coverage.

The grade estimation was validated by visual and statistical analysis and swath plots comparing the block grades with the composites.

Endeavour considers that the quality and spatial distribution of the data used, the geological continuity of the mineralisation and the quality of the estimated block model for the Vindaloo South deposit is sufficient for the reporting of Indicated and Inferred Mineral Resources in accordance with the CIM Definition Standards. Indicated Mineral Resources were typically defined in areas filled by the first estimation pass (five samples from a minimum of three holes within 50m) where there is a reasonable level of confidence in geological and grade continuity. Inferred Mineral Resources were typically defined in areas filled by the second estimation pass (three samples from a minimum of two holes within 100m) and where the controls on mineralisation are less well understood or the continuity is much reduced.

The Vindaloo South deposit has not been subjected to significant artisanal workings and therefore the MRE has not been depleted.

Mineral Resources are reported within a $1,500 optimised pit shell using a cut-off grade of 0.5 Au g/t. Technical and economic assumptions were made by Endeavour for mining factors (mining and selling costs, mining recovery and dilution, pit slope angles) and processing factors (gold recovery, processing costs) which were used for optimisation as summarised below:

• Base Mining cost: 2.00 (US$/t)
• Mining & Haulage cost: Oxide: 2.60 (US$/t); Transition: 3.20 (US$/t); Fresh: 3.60 (US$/t)
• Processing and G&A cost: Oxide: 14.00 (US$/t); Transition: 15.00 (US$/t); Fresh: 18.00 (US$/t)
• Selling cost: 80.00 (US$/oz Au)
• Mining recovery: 95%
• Mining dilution: 0%
• Processing recovery: 90%
• Slope angles: 40°

SABODALA-MASSAWAMINE

MassawaCentral Zonegeology and resource modelling

The orebodies, hosted by volcaniclastics, sediments, as well as mafic and felsic intrusives, are controlled by multiple subvertical anastamosed brittle-ductile shear zones, up to 25m wide.

The multiphase mineralization typically consists of early arsenopyrite-pyrite dissemination associated with pervasive silicification, overprinted by late quartz-stibnite veins with coarse gold, locally marked by carbonate-sericite alteration. Within Massawa Central Zone, the mineralisation style generally becomes more refractory towards the north, associated with higher arsenopyrite content and a change in host lithology from volcaniclastics to sediments.

There is a deposit scale correlation between increasing brittle-ductile strain and increasing gold grade, with the grade of mineralization variable along strike and down-dip related to the variable strain associated with the structural framework. The continuity of mineralization is localized along gabbro and felsic porphyry intrusive contacts with high-grade mineralization associated with high strain and arsenopyrite.

The grade and continuity of mineralization is now characterised by alteration style, deformation intensity, and intrusive contacts.

Low-grade (+1g/t Au) mineralisation is associated with weak to moderate shearing with silica-carbonate alteration and disseminated sulphides with weak strain. Arsenopyrite is rare. High-grade (+3g/t Au) mineralisation is associated with high strain including brecciation, extensional and shear veins, with moderate to strong silica-carbonate alteration and sulphides. Arsenopyrite is the dominant sulphide associated with gold, with arsenopyrite and pyrite also observed as vein selvages often containing visible gold.

Veins vary in style and include extensional, sheared, and boudinage Veining associated with +1g/t Au mineralisation is sub-parallel in orientation to primary strain highlighting the genetic link between deformation and mineralisation.

The statistical analysis, geological modelling and resource estimation were prepared by Endeavour resource staff. The Qualified Person, as defined by NI 43-101, that is taking responsibility for the statistical analysis, geological modelling and resource estimation is
Kevin Harris, CPG, Vice President Resources for Endeavour.

The Massawa CZ Mineral Resource model was developed in Seequent’s Leapfrog Geo software and Maptek’s Vulcan software. The database used to generate the Mineral Resources comprised some 2,567 drillholes, with a total of 263,953m drilled. All drilling was supported by industry standard quality assurance and quality control systems, with quality control sampling comprising blanks, coarse blanks, certified reference materials, and field and pulp duplicates. The QAQC data was reviewed and considered the assay data to be suitable for use in the subsequent Mineral Resource estimate.

One hundred and seventy-two mineralisation domains were modelled from interpreted from cross sections. The gold assays from the drill holes were composited to 1.0m intervals. Capping varied depending on the mineralised domain, between 20 g/t Au and 300 g/t Au. Spatial analysis of the gold distribution within the mineralised zone indicated good continuity of the grades along strike and down dip within the mineralised zones. Variogram ranges in the direction of maximum continuity were between 45m and 65m.

Density measurements from 4,704 samples from the core drillholes and covering each of the lithologies, were averaged based on the lithology and weathering zone. Average density values were applied to the associated portions of the block model as outlined below:

• Laterite: 1.87 g/cm³
• Un-mineralised Saprolite: 1.88 g/cm³; Mineralised Saprolite: 1.90 g/cm³
• Un-mineralised Saprock: 2.45 g/cm³; Mineralised Saprock: 2.4 g/cm³
• Un-mineralised Fresh: QFP 2.75 g/cm³,Gabbro-Mafic 2.5 g/cm³, Volcanics 2.77 g/cm3,Grewacke 2.78 g/cm³, Mineralisation 2.81g/cm³

Gold grades were estimated using Ordinary Kriging for the modelled mineralisation. In addition to gold, arsenic, sulphide sulphur, antimony and iron values were also estimated within the mineralised zones using an Inverse Distance Squared (“IDW3”) interpolation. The grade was estimated in multiple passes to define the higher confidence areas and extend the grade to the interpreted mineralised zone extents.

The grade estimation was validated with visual and statistical analysis, and comparison with the drilling data on sections with swath plots comparing the block grades with the composites.

Endeavour considers that the quality and spatial distribution of the data used, the geological continuity of the mineralisation and the quality of the estimated block model for Massawa CZ deposit is sufficient for the reporting of Indicated and Inferred Mineral Resources, in accordance with the CIM Definition Standards. Measured Mineral Resources have typically been defined in areas with a drillhole spacing of 10m, Indicated Mineral Resource were defined within a 30m drill spacing, where there is a reasonable level of confidence in geological and grade continuity. Inferred Mineral Resources have typically been defined in areas with a drillhole spacing of 60m, and where the controls on mineralisation are less well understood, or the continuity is much reduced.

Mineral Resources are reported within a $1,500 optimised pit shell. The estimated cut-off grades at Massawa are 0.34 g/t Au for oxide mineralisation to 1.04 g/t Au for transition and fresh rock mineralisation.

Basic pit optimization parameters used are defined below:

• Base mining cost: 2.35 (US$/t)
• Oxide mining cost (including haulage): 5.69 (US$/t)
• Transition mining cost (including haulage): 5.92 (US$/t)
• Fresh mining cost (including haulage): 5.92 (US$/t)
• Processing cost + G&A: Oxide 18.87 (US$/t); Transition: 45.79 (US$/t); Fresh: 45.79 (US$/t)
• Royalties, refining and selling cost: 80 (US$/oz Au)
• Mining recovery: 95%
• Processing recovery: Oxide 93%; Transition 88.3%; Fresh 88.3%
• Average slope angles: 35-45°

Massawa North Zonegeology and resource modelling

The Massawa North Zone consists of a main NNE trending mineralised structure with discontinuous footwall and hanging wall lodes. Mineralization is localised in a damage zone adjacent to highly strained bands of fine- to medium grained felsic and lithic wacke, wacke with subordinate carbonaceous shales, and gabbros. The Massawa North Zone is subdivided into a southern zone which hosts discontinuous, weaker gold mineralization (average grade of 1 g/t Au to 1.5 g/t Au). The weakly silicified, brittle-ductile, mineralised shear is less than 10m in thickness and is sub-vertical dipping to the ESE. The higher-grade but narrow mineralisation is focused at the margins of a medium-grained greywacke and lithological contacts with contrasting grain size. The northern zone is the highest grade (>4 g/t Au) portion of the deposit. Mineralization is predominately confined to a continuous, narrow zone up to 15m thick, which is sub-vertical and dipping to the WNW. The mineralisation is bounded by two prominent carbonaceous shale horizons within the sedimentary sequence.

The orebodies, entirely hosted by deformed sedimentary units (dominant metagreywacke), are mostly controlled by a single discontinuous and bifurcating subvertical brittle-ductile shear.

The mineralization consists of early arsenopyrite-pyrite dissemination and stringers networks (no coarse visible gold) generally marked by a strong silica-carbonate-sericite alteration. The alteration is mainly composed of sericite, carbonate and chlorite alteration affecting both the sedimentary rocks and the gabbro unit. Primary and tectonic rock fabrics are often still clearly visible. The gold is largely refractory.

Two mineralised domains are modelled in the NZ:

1. A higher-grade domain (average 5 g/t Au) consisting of 7% to 10% disseminated sulphides (arsenopyrite>pyrite) associated with ductile shearing with extensional quartz-carbonate veins.

2. A lower-grade domain (average 1.5 g/t Au) consisting of 1% to 3% disseminated sulphides (pyrite>arsenopyrite) associated with brecciation and extensional quartz-carbonate veins.

The statistical analysis, geological modelling and resource estimation was prepared by SLR Consulting. The Qualified Person, as defined by NI 43-101, that is taking responsibility for the statistical analysis, geological modelling and resource estimation is
Kevin Harris, CPG, Vice President Resources for Endeavour.

The Massawa NZ Mineral Resource model was developed in Seequent’s Leapfrog Geo software and Maptek’s Vulcan software. The database used to generate the Mineral Resources comprised some 920 drillholes, with a total of 108,436m drilled. All drilling was supported by industry standard quality assurance and quality control systems, with quality control sampling comprising blanks, coarse blanks, certified reference materials, and field and pulp duplicates. The QAQC data was reviewed and considered the assay data to be suitable for use in the subsequent Mineral Resource estimate.

Fifty mineralisation domains were modelled in Leapfrog Geo and interpreted from cross sections. The gold assays from the drill holes were composited to 1.0m intervals. Capping varied depending on the mineralised domain, between 10 g/t Au and 55 g/t Au. Spatial analysis of the gold distribution within the mineralised zone indicated good continuity of the grades along strike and down dip within the mineralised zones. Variogram ranges in the direction of maximum continuity were between 50m and 120m.

Density measurements from 4,593 samples from the core drillholes and covering each of the lithologies, were averaged based on the lithology and weathering zone. Average density values were applied to the associated portions of the block model as outlined below:

• Laterite: 1.87 g/cm³
• Saprolite: 1.90 g/cm³
• Saprock: QFP 2.29 g/cm³,Gabbro-Mafic 2.33 g/cm³, Volcanics 2.31 g/cm³, Greywacke 2.24g/cm³ Schist 2.26 g/cm³
• Fresh: QFP 2.72 g/cm³,Gabbro-Mafic 2.85 g/cm³, Volcanics 2.74 g/cm³, Greywacke 2.75 g/cm³ Schist 2.72 g/cm³

Gold grades were estimated using Ordinary Kriging for the modelled mineralisation. In addition to gold, arsenic, sulphide sulphur, antimony and iron values were also estimated within the mineralised zones using an Inverse Distance Squared (“IDW3”) interpolation. The grade was estimated in multiple passes to define the higher confidence areas and extend the grade to the interpreted mineralised zone extents.

The grade estimation was validated with visual and statistical analysis, and comparison with the drilling data on sections with swath plots comparing the block grades with the composites.

Endeavour considers that the quality and spatial distribution of the data used, the geological continuity of the mineralisation and the quality of the estimated block model for Massawa NZ deposit is sufficient for the reporting of Indicated and Inferred Mineral Resources, in accordance with the CIM Definition Standards. Measured Mineral Resources have typically been defined in areas with a drillhole spacing of 20m, Indicated Mineral Resource were defined within a 50m drill spacing, where there is a reasonable level of confidence in geological and grade continuity. Inferred Mineral Resources have typically been defined in areas with a drillhole spacing of 100m, and where the controls on mineralisation are less well understood, or the continuity is much reduced.

Mineral Resources are reported within a $1,500 optimised pit shell. The estimated cut-off grades at Massawa NZ are 0.34 g/t Au for oxide mineralisation to 0.98 g/t Au for transition and fresh rock mineralisation.

Basic pit optimization parameters used are defined below:

• Base mining cost: 2.40 (US$/t)
• Oxide mining cost (including haulage): 5.71 (US$/t)
• Transition mining cost (including haulage): 5.97 (US$/t)
• Fresh mining cost (including haulage): 5.97 (US$/t)
• Processing cost + G&A: Oxide 18.52 (US$/t); Transition: 45.38 (US$/t); Fresh: 45.38 (US$/t)
• Royalties, refining and selling cost: 80 (US$/oz Au)
• Mining recovery: 95%
• Processing recovery: Oxide 85%; Transition 88.3%; Fresh 88.3%
• Average slope angles: 35-45°

Sofia geology and resource modelling

The Sofia North Extension target is located within the prolific Sofia-Sabodala shear corridor, immediately north of the Sofia North pit, approximately 20km south of the Sabodala deposit.

Sofia North consists of one main NNE trending mineralised structure and a discontinuous footwall lode. The gold mineralization, associated with quartz-diorite dikes, is controlled by multiple anastamosed and steeply dipping brittle-ductile shear structures, generally quite narrow but up to 25m thick within local dilation zones. The mineralised bodies are marked by moderate to strong albite-silica pervasive alteration, dense quartz-carbonate veining, and abundant disseminated pyrite. The main mineralised structure is developed at the major eastern contact of the gabbros that change in strike from N040⁰ to N010⁰ and has been delineated for more than 2km. The structure is strike continuous from Sofia Main. The structure is steep and dipping to the west. At Sofia North, the diorite is comparatively narrower compared to Sofia Main with elevated grades above the weathering profile suggesting a supergene influence. A second, high-grade (>5 g/t Au) but narrow mineralised zone is hosted in silica carbonate veins commonly developed within the hanging wall lithological contacts, suggesting that the strain has transferred from the footwall at Sofia Main to the hanging wall at Sofia North.

The mineralisation is defined by a strong occurrence of fine disseminated pyrite accompanied by strong quartz, albite, and carbonate alteration. Mineralization occurs in quartz-albite altered intermediate intrusives as at Sofia Main, with quartz ± magnetite ± chlorite. Vein hosted mineralization in the mafic host is spatially associated with chlorite-rich shears with silica carbonate veining.

The statistical analysis, geological modelling and Resource estimation were prepared by Endeavour. The Qualified Person, as defined by NI 43-101, that is taking responsibility for the statistical analysis, geological modelling and resource estimation is Mr Joseph Hirst B.Sc, M.Sc. EurGeol. CGeol. FGS; a Resource Geologist with Endeavour.

The Sofia Mineral Resource model was developed in Seequent’s Leapfrog Geo and Datamine software. The database used to generate the Mineral Resources comprised some 455 drillholes, with a total drilling meterage of 29,805m. All drilling was supported by industry standard quality assurance and quality control systems, with quality control sampling comprising blanks, coarse blanks, certified reference materials, and field and pulp duplicates. Endeavour has reviewed the QAQC data available and considers the assay data to be suitable to support a Mineral Resource estimate.

Mineralisation domains were modelled implicitly, using an economic composite target of 0.4 g/t Au at 2m for mineralised interval selection per identified mineralised structures. For the estimate the gold assays from the drill holes were composited to 1.0m intervals as this was the mean sample length. Capping varied depending on the mineralised domain, between 25 and 40g/t Au.

Density measurements from 541 samples from drillholes covering each of the oxidation states, were averaged based on the material type. Average density values were applied to the associated portions of the block model as outlined below:

• Fresh: 2.76 g/cm³
• Weakly Oxidised: 2.65 g/cm³
• Moderately Oxidised: 2.20 g/cm³
• Strongly Oxidised: 1.83 g/cm³

Gold grades were estimated using inverse distance weighting (2nd power) for the modelled mineralisation. The grade was estimated in multiple passes to define the higher confidence areas and extend the grade to the interpreted mineralised zone extents.

The grade estimation was validated with visual and statistical analysis, and comparison with the drilling data on sections with swath plots comparing the block grades with the composites.

Endeavour considers that the quality and spatial distribution of the data used, the geological continuity of the mineralisation and the quality of the estimated block model for Sofia deposit is sufficient for the reporting of Indicated and Inferred Mineral Resources, in accordance with the CIM Definition Standards. Indicated Mineral Resources have typically been defined in areas with a drillhole spacing of 20-40 m along sections, and 40-50 m between sections, with multiple pierce points per individual structure both along strike and down dip where there is a reasonable level of confidence in geological and grade continuity. Inferred Mineral Resources have typically been defined in areas with a drillhole spacing of 50 to 75 m, and where the controls on mineralisation are less well understood, or the continuity is much reduced.

Mineral Resources are reported within an optimised pit shell using cut-off of grades of 0.55 g/t Au for oxide (laterite-saprolite); and 0.51 g/t Au for transition and fresh, which reflect the marginal cut-off grades for processing determined during the pit optimisation. Technical and economic assumptions were developed by Endeavour for mining factors (mining and selling costs, mining recovery and dilution, pit slope angles) and processing factors (gold recovery, processing costs), which were used for optimisation. These factors are summarised below:

• Base mining cost: 2.00 (US$/t)
• Oxide mining cost (including haulage): 4.00 (US$/t)
• Transition mining cost (including haulage): 5.00 (US$/t)
• Fresh mining cost (including haulage): 5.00 (US$/t)
• Processing cost+G&A: Oxide 12.00 (US$/t); Transition: 14.00 (US$/t); Fresh: 16.00 (US$/t)
• Selling cost: 80 (US$/oz Au)
• Mining recovery: 95%
• Processing recovery: Oxide 90%; Transition 90%; Fresh 40%
• Average slope angles: 40°

Tina geology and resource modelling

The Tina deposit is located 24km south of the Sabodala mill within the Bakan structural corridor, a major western splay of the Main Transcurrent Shear Zone (MTZ), where mineralisation is controlled by the Kossanto Shear

During 2021, exploration efforts were mainly focused on extending mineralistion towards the north and the east by grid drilling the resource at 40x40m spacing in these directions. In addition, a series of 120-240m step-out profiles were drilled to test the extent of the mineralised trend.

The main gold mineralisation system is centered on a deformed granodiorite body, up to 120m wide, that intrudes metasedimentary units. The felsic intrusion has been deformed by a series of subparallel brittle ductile shears that are up to 60m thick and steeply dipping to the east. The weathering profile does not exceed 30m depth at Tina, hence mineralisation is predominantly made up of fresh ore.

The dominant low-grade mineralization, associated with moderate to strong pervasive sericite-silica alteration and dense quartz-carbonate veining, is marked by pyrite-arsenopyrite ± stibnite stringer veins and disseminations.

The statistical analysis, geological modelling and resource estimation were prepared by Endeavour resource staff. The Qualified Person, as defined by NI 43-101, that is taking responsibility for the statistical analysis, geological modelling and resource estimation is
Kevin Harris, CPG, Vice President Resources for Endeavour.

The Tina Mineral Resource model was developed in Geovia’s Surpac software. The database used to generate the Mineral Resources comprised some 159 drillholes, with a total of 20,750m drilled. All drilling is supported by industry standard quality assurance and quality control systems, with quality control sampling comprising blanks, coarse blanks, certified reference materials, and field and pulp duplicates. The QAQC data was reviewed and considered the assay data to be suitable for use in the subsequent Mineral Resource estimate.

Ten mineralisation domains were modelled from interpreted cross sections. The gold assays from the drill holes were composited to 1.0m intervals. Capping varied depending on the mineralised domain, between no cap and 12g/t. Spatial analysis of the gold distribution within the mineralised zone indicated good continuity of the grades along strike and down dip within the mineralised zones. Variogram ranges in the direction of maximum continuity were between 45m and 65m.

Density measurements from 789 samples from the core drillholes and covering each of the lithologies, were averaged based on the weathering zone. Average density values were applied to the associated portions of the block model as outlined below:

• Laterite: 2.00 g/cm³
• Saprolite: 1.80 g/cm³
• Saprock: 2.25 g/cm³
• Fresh: 2.77 g/cm³

Gold grades were estimated using an Inverse Distance Squared (“IDW2”) for estimator of the modelled mineralisation. The grade was estimated in multiple passes to define the higher confidence areas and extend the grade to the interpreted mineralised zone extents.

The grade estimation was validated with visual and statistical analysis, and comparison with the drilling data on sections with swath plots comparing the block grades with the composites.

Endeavour considers that the quality and spatial distribution of the data used, the geological continuity of the mineralisation and the quality of the estimated block model for La Plaque deposit is sufficient for the reporting of Indicated and Inferred Mineral Resources, in accordance with the CIM Definition Standards. Indicated Mineral Resources have typically been defined in areas with a drillhole spacing of 25m along sections, and 40-50 m between sections, where there is a reasonable level of confidence in geological and grade continuity. Inferred Mineral Resources have typically been defined in areas with a drillhole spacing of 50 to 75m, and where the controls on mineralisation are less well understood, or the continuity is much reduced.

Mineral Resources are reported within a $1,500 optimised pit shell using cut-off of grades of 0.5 g/t. Basic pit optimization parameters used are defined below:

• Base mining cost: 2.35 (US$/t)
• Oxide mining cost (including haulage): 7.00 (US$/t)
• Transition mining cost (including haulage): 7.20 (US$/t)
• Fresh mining cost (including haulage): 7.50 (US$/t)
• Processing cost + G&A: Oxide 14.00 (US$/t); Transition: 40.32 (US$/t); Fresh: 40.40 (US$/t)
• Selling cost: 50 (US$/oz Au)
• Mining recovery: 95%
• Processing recovery: Oxide 92%; Transition 85%; Fresh 85%
• Average slope angles: 40°

Samina geology and resource modelling

The main gold mineralisation system at Samina is centered on an up to twenty meters thick silica fault-breccia developed east of the contact zone between a gabbro intrusive and a metasedimentary unit. The contact zone is steeply dipping to the northwest. Oxide ore potential is related to the weathering profile and has been observed to over 100m depth along the fault-breccia. In relation to this main structure, five northeast striking and sub-parallel mineralised zones have been identified within both hanging wall and footwall of the lithostructural corridor.

The mineralisation at Samina is associated with strong pervasive haematite-sericite-silica alteration and dense quartz veining. Mineralisation is also associated with boxworks of disseminated pyrite and arsenopyrite.

The recent drilling program has already resulted in better delineation and continuity confirmation of the higher grade central main mineralised system. In addition the drill program has resulted in the extension of some of the mineralised structures towards the south, and in the discovery of some new footwall mineralised occurrences in coarse-grained metasediment units towards the east.

The statistical analysis, geological modelling and resource estimation were prepared Endeavour resource staff. The Qualified Person, as defined by NI 43-101, that is taking responsibility for the statistical analysis, geological modelling and resource estimation is Kevin Harris, CPG, Vice President Resources for Endeavour.

The Samina Mineral Resource model was developed in Seequent’s Leapfrog Geo and Geovia’s Surpac software. The database used to generate the Mineral Resources comprised some 237 drillholes, with a total of 29,823 meters drilled. All drilling is supported by industry standard quality assurance and quality control systems, with quality control sampling comprising blanks, coarse blanks, certified reference materials, and field and pulp duplicates. The QAQC data was reviewed and considered the assay data to be suitable for use in the subsequent Mineral Resource estimate.

Eight mineralisation domains were modelled in Leapfrog Geo using the vein tools and cross-section interpretations. The gold assays from the drill holes were composited to 1.0m intervals. Capping varied depending on the mineralised domain, between 6 g/t Au and 25 g/t Au. Spatial analysis of the gold distribution within the mineralised zone indicated good continuity of the grades along strike and down dip within the mineralised zones. Variogram ranges in the direction of maximum continuity were between 40m and 60m.

Density measurements from 332 samples from the core drillholes and covering each of the lithologies, were averaged based on the weathering zone. Average density values were applied to the associated portions of the block model as outlined below:

• Laterite: 2.00 g/cm³
• Saprolite: 1.90 g/cm³
• Saprock: 2.30 g/cm³
• Fresh: 2.77 g/cm³

Gold grades were estimated an Inverse Distance Squared (“IDW2”) estimator of the modelled mineralisation. The grade was estimated in multiple passes to define the higher confidence areas and extend the grade to the interpreted mineralised zone extents.

The grade estimation was validated with visual and statistical analysis, and comparison with the drilling data on sections with swath plots comparing the block grades with the composites.

Endeavour considers that the quality and spatial distribution of the data used, the geological continuity of the mineralisation and the quality of the estimated block model for Samina deposit is sufficient for the reporting of Indicated and Inferred Mineral Resources, in accordance with the CIM Definition Standards. Indicated Mineral Resources have typically been defined in areas with a drillhole spacing of 20-30 m along sections, and 40-50m between sections, where there is a reasonable level of confidence in geological and grade continuity. Inferred Mineral Resources have typically been defined in areas with a drillhole spacing of 50 to 75m, and where the controls on mineralisation are less well understood, or the continuity is much reduced.

Mineral Resources are reported within a $1,500 optimised pit shell using cut-off of grades of 0.5 g/t. Basic pit optimization parameters used are defined below:

• Base mining cost: 2.35 (US$/t)
• Oxide mining cost (including haulage): 8.12 (US$/t)
• Transition mining cost (including haulage): 8.35 (US$/t)
• Fresh mining cost (including haulage): 8.64 (US$/t)
• Processing cost+G&A: Oxide 14.00 (US$/t); Transition: 40.32 (US$/t); Fresh: 40.40 (US$/t)
• Selling cost: 50 (US$/oz Au)
• Mining recovery: 95%
• Processing recovery: Oxide 92%; Transition 85%; Fresh 85%
• Average slope angles: 40°

Delyageology and resource modelling

The lithological sequence at Delya is composed of massive and foliated andesite to the west, and an eastern sedimentary package consisting of shales, carbonaceous shales, lithic, and feldspar-wacke. These units are intruded by a wide gabbro unit. These lithologies have undergone strong ductile deformation, with structures trending NE (030° to 040°) and steeply dipping to the east.

The main Delya mineralised structure is located at the contact between the gabbro and the sedimentary package and is bounded by two carbonaceous shale units. Three parallel zones of mineralisation have been defined at Delya, with the main zone of mineralisation being hosted at the lower margin of the gabbro intrusive within a highly sheared, silicified and sericitized schist.

The mineralised zone varies in thickness up to 10m, contains zones of local higher grades, and steeply dips to the east. The other branches located to the west have a similarly steep dip to the west.

The mineralization, hosted in hydrothermal breccia along a brittle-ductile sheared contact zone between volcanics and sediments (interbedded graphitic schists), consists in abundant pyrite-arsenopyrite disseminations and veinlets associated with moderate to strong silica-sericite-carbonate-(fuchsite) alteration.

The statistical analysis, geological modelling and resource estimation was prepared by Endeavour resource staff. The Qualified Person, as defined by NI 43-101, that is taking responsibility for the statistical analysis, geological modelling and resource estimation is
Kevin Harris, CPG, Vice President Resources for Endeavour.

The Delya Mineral Resource model was developed in Seequent’s Leapfrog Geo software and Maptek’s Vulcan software. The database used to generate the Mineral Resources comprised some 162 drillholes, with a total of 14,739m drilled. All drilling was supported by industry standard quality assurance and quality control systems, with quality control sampling comprising blanks, coarse blanks, certified reference materials, and field and pulp duplicates. The QAQC data was reviewed and considered the assay data to be suitable for use in the subsequent Mineral Resource estimate.

Six mineralisation domains were modelled from in Leapfrog Geo and interpreted from cross sections. The gold assays from the drill holes were composited to 1.0m intervals. Capping varied depending on the mineralised domain, between 8 g/t Au and 30 g/t Au. Spatial analysis of the gold distribution within the mineralised zone indicated good continuity of the grades along strike and down dip within the mineralised zones. Variogram ranges in the direction of maximum continuity were 55m.

Density measurements from 1,128 samples from the core drillholes and covering each of the lithologies, were averaged based on the lithology and weathering zone. Average density values were applied to the associated portions of the block model as outlined below:

• Saprolite: Carbonaceous Shale 2.02 g/cm³, Mafic 1.87 g/cm³, Chert 2.04 g/cm³, Greywacke 1.78g/cm³, Schist 2.02 g/cm³, Andesite 2.20 g/cm³ ,Mineralisation 2.09 g/cm³
• Saprock: Carbonaceous Shale 2.46 g/cm³, Mafic 2.38 g/cm³, Chert 2.69 g/cm³, Greywacke 2.54/cm³, Schist 2.58 g/cm³, Andesite 2.76 g/cm³ ,Mineralisation 2.40 g/cm³
• Fresh Carbonaceous Shale 2.81 g/cm³, Mafic 2.82 g/cm³, Chert 2.81 g/cm³, Greywacke 2.71/cm³, Schist 2.84 g/cm³, Andesite 2.87 g/cm³ ,Dolerite 2.88 g/cm³ ,Mineralisation 2.83 g/cm³

 
Gold grades were estimated using Ordinary Kriging for the modelled mineralisation. In addition to gold, arsenic, sulphide sulphur, antimony and iron values were also estimated within the mineralised zones using inverse distance cube interpolation. The grade was estimated in multiple passes to define the higher confidence areas and extend the grade to the interpreted mineralised zone extents.

The grade estimation was validated with visual and statistical analysis, and comparison with the drilling data on sections with swath plots comparing the block grades with the composites.

Endeavour considers that the quality and spatial distribution of the data used, the geological continuity of the mineralisation and the quality of the estimated block model for Delya deposit is sufficient for the reporting of Indicated and Inferred Mineral Resources, in accordance with the CIM Definition Standards. Indicated Mineral Resource were defined within a 22.5m drill spacing, where there is a reasonable level of confidence in geological and grade continuity. Inferred Mineral Resources have typically been defined in areas with a drillhole spacing of 55m, and where the controls on mineralisation are less well understood, or the continuity is much reduced.

Mineral Resources are reported within a $1,500 optimised pit shell. The estimated cut-off grades at Delya are 0.31 g/t Au for oxide mineralisation to 1.00 g/t Au for transition and fresh rock mineralisation.

Basic pit optimization parameters used are defined below:

• Base mining cost: 2.405 (US$/t)
• Oxide mining cost (including haulage): 6.35(US$/t)
• Transition mining cost (including haulage): 6.62 (US$/t)
• Fresh mining cost (including haulage): 6.62 (US$/t)
• Processing cost + G&A: Oxide 13.34 (US$/t); Transition: 43.97 (US$/t); Fresh: 43.97 (US$/t)
• Royalties, refining and selling cost: 80 (US$/oz Au)
• Mining recovery: 95%
• Processing recovery: Oxide 93%; Transition 88.3%; Fresh 88.3%
• Average slope angles: 35-45°

LAFIGUÉ DEPOSIT – FETEKRO PROPERTY

Lafiguégeology and resource modelling

The Lafigué deposit is hosted by a Birimian volcanic complex affected by a transpressive deformation and intruded by granodioritic bodies and quartz-porphyry dykes. The mineralisation is mainly controlled by an ENE-trending brittle-ductile thrust fault dipping 15° to 45° SSE. Mineralisation is mainly hosted by a network of Qz-Cb-To-Py-Po±Visible Gold quartz veins within sheared and altered brittle-ductile deformation zones of various thickness. The alteration assemblage comprises Bt-Ser±To±Chl±Cb and various amounts of disseminated Pyrrhotite and Pyrite (up to 5%).  

The shear zones are better developed at or near lithological contacts, where competency contrasts favour the brittle-ductile shearing and enhanced hydrothermal fluid flow. The veins are emplaced in the deformation corridors both along CS and S planes.  

At Junction Lafigué Centre – Lafigué Nord, the prominent deformation zone is typically located at the contact zone between a mafic intrusive (gabbro) and mafic volcanics, whereby the contact also occurs with a felsic intrusive at Lafigué Nord. The shear bands are localised preferably at the edges of a granodioritic intrusive or at a basalt/gabbro interface and crosscut the main regional foliation.

Within the Lafigué deposit, the recent Junction Lafigué Centre – Lafigué Nord drilling successfully recognized new mineralization over 400 meters along ENE axis and demonstrated the SSE down dip extension over 700m. At Lafigué Nord, recent drilling was mainly targeting deep orebodies close to initial 2020 pit design limits targeting some additional open pitable indicated resources. In all cases, mineralisation remains open at depth and will be a longer-term target for possible UG mining.

The statistical analysis, geological modelling and resource estimation were prepared by a team of consultants from SRK Consulting (UK) Ltd. The Qualified Person, as defined by NI 43-101, that is taking responsibility for the statistical analysis, geological modelling and resource estimation is Dr
Lucy Roberts, Principal Consultant (Resource Geology) with SRK.

The Lafigué Mineral Resource model was developed in Seequent’s Leapfrog Geo software. The database used to generate the Mineral Resources comprised some 1,546 drillholes, with a total drilling meterage of 252,660m. All drilling was supported by industry standard quality assurance and quality control systems, with quality control sampling comprising blanks, coarse blanks, certified reference materials, and field and pulp duplicates. SRK has reviewed the QAQC data available and considers the assay data to be suitable for use in the subsequent Mineral Resource estimate.

Mineralisation domains were modelled implicitly, using an indicator interpolant for areas of wider, more continuous mineralisation, and vein wireframes for zones of less continuous mineralisation. The gold assays from the drill holes were composited to 1.0m intervals. Capping varied depending on the mineralised domain, between no cap and 40g/t. Spatial analysis of the gold distribution within the mineralised zone indicated good continuity of the grades along strike and down dip within the mineralised zones. Variogram ranges in the direction of maximum continuity were between 45m and 75m.

Density measurements from 236 drillholes and covering each of the lithologies, were averaged based on the material type (and lithology, in the case of fresh material). Average density values were applied to the associated portions of the block model as outlined below:

• Laterite: 2.00 g/cm³
• Saprolite: 1.66 g/cm³
• Saprock: 2.51 g/cm³
• Fresh – Mafic: 2.86 g/cm³
• Fresh – Felsic: 2.72 g/cm³

 
Gold grades were estimated using Ordinary Kriging for the majority of the modelled mineralisation. Where it was not possible to define a well-structured variogram for the smallest domains with low sample support, an Inverse Distance Squared (“IDW2”) estimator was used. The grade was estimated in multiple passes to define the higher confidence areas and extend the grade to the interpreted mineralised zone extents.

The grade estimation was validated with visual and statistical analysis, and comparison with the drilling data on sections with swath plots comparing the block grades with the composites.

SRK considers that the quality and spatial distribution of the data used, the geological continuity of the mineralisation and the quality of the estimated block model for Lafigué deposit is sufficient for the reporting of Indicated and Inferred Mineral Resources, in accordance with the CIM Definition Standards. Indicated Mineral Resources have typically been defined in areas with a drillhole spacing of 20-40m along sections, and 40-50m between sections, where there is a reasonable level of confidence in geological and grade continuity. Inferred Mineral Resources have typically been defined in areas with a drillhole spacing of 50 to 75m, and where the controls on mineralisation are less well understood, or the continuity is much reduced.

Given the limited artisanal mining which occurred before the area was fenced and artisanal miners were removed, SRK depleted the declared Mineral Resources to reflect an estimated 50,000 ounces of depletion due to artisanal mining. A drone survey was conducted on 17 August 2021 and covered the full extent of the area impacted by artisanal mining. The drone survey identified areas which had been mined using open pit methods, with pits of up to 10m deep being observed. The drone survey was used to deplete these areas. In addition, underground mining activities were also identified, which cannot be captured by the drone survey. To reflect the underground activity, grades in the block model modelled as mineralised material within 5m of the pre-mining topographic surface (dated 2015), outside of, and below, where required, the drone survey voids, have been reduced to zero. The 5m depth assumption is based on observations by Endeavour personnel in the field. In the absence of any underground survey, and to reflect the uncertainty for these areas, SRK has not depleted the tonnages. This area remains a risk to the Mineral Resource and requires further detailed investigation as part of the next phase of the study.

Mineral Resources are reported within an optimised pit shell using cut-off of grades of 0.4 g/t Au (oxide); 0.5 g/t Au (transition) and 0.5 g/t Au (fresh), which reflect the marginal cut-off grades for CIL processing determined during the pit optimisation. Technical and economic assumptions were agreed between SRK and Endeavour for mining factors (mining and selling costs, mining recovery and dilution, pit slope angles) and processing factors (gold recovery, processing costs), which were used for optimisation. These factors were developed as part of the ongoing Feasibility Study for the Lafigué project, as summarised below:

• Mining cost: 2.12 (US$/t)
• Waste mining cost: 2.65 (US$/t)
• Processing cost: Oxide/Transition: 7.47 (US$/t); Fresh: 9.13 (US$/t)
• Selling cost: 71.8 (US$/oz Au)
• Mining recovery: 98%
• Mining dilution: 9%
• Processing recovery: Varies between 82-97%, dependent on head grade
• Average slope angles: 33-51°, dependent on geotechnical domain
• G&A cost: 5.60 (US$/tore)
• Discount rate: 5%

QUALIFIED PERSONS

Jonathan Lawrence (FAIG, MAusIMM), Vice President Exploration - Burkina Faso for Endeavour, has reviewed and approved the technical information in this news release. Jonathan has more than 20 years of mineral exploration and mining experience and is a "Qualified Person" as defined by National Instrument 43-101 – Standards of Disclosure for Mineral Projects ("NI 43-101").

CONTACT INFORMATION

ABOUT ENDEAVOURMINING CORPORATION

Endeavour Mining is one of the world’s senior gold producers and the largest in West Africa, with operating assets across Senegal, Cote d’Ivoire and Burkina Faso and a strong portfolio of advanced development projects and exploration assets in the highly prospective Birimian Greenstone Belt across West Africa.

A member of the World Gold Council, Endeavour is committed to the principles of responsible mining and delivering sustainable value to its employees, stakeholders and the communities where it operates. Endeavour is listed on the London Stock Exchange and the Toronto Stock Exchange, under the symbol EDV.

For more information, please visit: www.endeavourmining.com.

This news release contains "forward-looking statements" including but not limited to, statements with respect to Endeavour's plans and operating performance, the estimation of mineral reserves and resources, the timing and amount of estimated future production, costs of future production, future capital expenditures, and the success of exploration activities. Generally, these forward-looking statements can be identified by the use of forward-looking terminology such as "expects", "expected", "budgeted", "forecasts", and "anticipates". Forward-looking statements, while based on management's best estimates and assumptions, are subject to risks and uncertainties that may cause actual results to be materially different from those expressed or implied by such forward-looking statements, including but not limited to: risks related to the successful integration of acquisitions; risks related to international operations; risks related to general economic conditions and credit availability, actual results of current exploration activities, unanticipated reclamation expenses; changes in project parameters as plans continue to be refined; fluctuations in prices of metals including gold; fluctuations in foreign currency exchange rates, increases in market prices of mining consumables, possible variations in ore reserves, grade or recovery rates; failure of plant, equipment or processes to operate as anticipated; accidents, labour disputes, title disputes, claims and limitations on insurance coverage and other risks of the mining industry; delays in the completion of development or construction activities, changes in national and local government regulation of mining operations, tax rules and regulations, and political and economic developments in countries in which Endeavour operates. Although Endeavour has attempted to identify important factors that could cause actual results to differ materially from those contained in forward-looking statements, there may be other factors that cause results not to be as anticipated, estimated or intended. There can be no assurance that such statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements. Please refer to Endeavour's most recent Annual Information Form filed under its profile at www.sedar.com for further information respecting the risks affecting Endeavour and its business.

Attachment

• NR - Resource Update