Endeavour Grows The High-Grade Le Plaque Deposit At Its Ity Mine To 0.5MOZ

ENDEAVOUR GROWS THE HIGH-GRADE
LE PLAQUE DEPOSIT AT ITS ITY MINE TO 0.5MOZ

0.4Moz of Indicated resources added at >3 g/t Au  ·  $15/oz discovery cost  ·  7 new targets defined

 LE PLAQUE AREA HIGHLIGHTS:               

• Le Plaque Indicated resource has increased from 85koz to 476koz and has the potential to continue to significantly increase 
  • Continued low discovery cost of $15 per Indicated resource ounce, as over 85% of RC and DD holes drilled encountered at least one interval of mineralization of 0.5g/t Au with a minimum of more than 2m
  • Ity mine M&I resource up 11% with significantly higher grade added as Le Plaque’s grade is 3.20 g/t Au compared to 1.54 g/t Au for the Ity mine  
  • Drilling encountered numerous very high-grade intercepts of 10 g/t Au over 5 to 10m, including a company-wide record intercept of 11.7m at 106 g/t Au (true width, hole: FL18-709)
  • The Le Plaque deposit is now composed of 3 zones (Le Plaque Main, Epsilon and Le Plaque South), all of which are open at depth and in multiple directions with mineralization confirmed by step-out drilling
  • Preliminary metallurgical tests indicate gold recovery rates of at least 90%
  • The Le Plaque drilling campaign is ongoing with at least 20,000m planned for H2-2019 with the aim of delineating further resources and reaching reserves status by year-end

• 7 additional nearby targets were identified following an extensive reconnaissance drilling campaign 
  • Since drilling began in Q1-2018, a strong focus has been placed on understanding the potential of the wider Le Plaque area; 413 holes were used for resource delineation out of the 1,361 holes drilled in the wider area
  • Reconnaissance drilling has outlined that Le Plaque only represents 20% of the large anomalic area located in the northern part of the Floleu license where at least 7 additional other targets were identified
  • Drilling is expected to continue in H2-2019 with a strong focus to delineate additional resources in 2020

Abidjan, July 8, 2019 – Endeavour Mining (TSX:EDV)(OTCQX:EDVMF) is pleased to announce a significant addition in high-grade resources at its previously announced Le Plaque discovery at its flagship Ity mine in Côte d’Ivoire and the definition of seven new targets which boost confidence in delineating further resources.

Patrick Bouisset, Executive Vice-President Exploration and Growth, stated: “We are very pleased with the maiden resource at Le Plaque as it confirms the high potential we see at Ity. Our results to date have been outstanding, both in terms of the very high grade nature and mineralization extension.

Looking ahead, we are excited by the potential in the Le Plaque area which remains open at depth and in several directions. Before year end, we expect to further increase its resource base and define a maiden reserve. In addition, we are extremely pleased with our ongoing reconnaissance drilling campaign as it has identified seven new targets which leaves us very well positioned to continue delineating further maiden resources in the large northern Floleu license anomalic area.

More broadly, the success we have achieved -- notably at Houndé, Ity and Fetekro -- just two and half years since the implementation of our 5-year strategic exploration plan in late 2016, demonstrates that we continue to add value while remaining on track to reach our ambitious discovery cost target of less than $20/oz.”

Le Plaque, located only 6km south of the processing plant, is a high-grade discovery made on the northern part of the wholly-owned Floleu exploration license, as shown in Figure 1 below.

 Figure 1 - Greater Ity General Map with Le Plaque Location

A maiden Indicated resource was delineated in early 2018 based on 124 holes drilled totalling 14,000 meters. As shown in Table 1 below, the Indicated resource has subsequently grown following 53,700 additional meters drilled consisting of 413 holes (comprised of 156 Diamond Drilling (“DD”) holes totalling 24,291 meters; 86 RC-DD holes totalling 15,327 meters; and 171 Reverse Circulation (“RC”) holes totalling 14,095 meters). Due to the intensive in-fill drill program completed, 90% of the maiden resource has been classified to the Indicated category. As the mineralization starts at surface, it is amenable to open pit mining.

Table 1: Le Plaque Mineral Resource Evolution

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 $1,500/oz Pit Shell and based on a cut-off of 0.5 g/t Au. For the notes related to the December 31, 2018 resource estimate, please consult the March 5, 2019 press release available on the Company’s website. For the notes related to the June 30, 2019 resource estimate, please consult the below section entitles Le Plaque Resource Modelling.

The Le Plaque deposit is now composed of 3 zones (Le Plaque Main, Epsilon and Le Plaque South), all of which are open in multiple directions with mineralization confirmed by step-out drilling. The Le Plaque updated resource stretches over at least 1.2km long and 0.2km wide for the Le Plaque Main and Epsilon areas, and over 0.6km long and 0.3km wide for the Le Plaque South area.

Drilling is ongoing in the Le Plaque area with at least 20,000 meters of additional drilling expected to be completed before year-end. The aim is to extend its mineralization and delineate additional resources, which are expected to be converted into reserves in Q4-2019.  

The updated Le Plaque resource estimate has to date increased Ity’s Measured and Indicated resources by 11%, as presented in Table 2 below, while adding significantly higher-grade material as Le Plaque’s grade is 3.20 g/t Au compared to 1.54 g/t Au for the Ity mine. 

Table 2: Ity Mine Mineral Resource Evolution

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 $1,500/oz Pit Shell and based on a cut-off of 0.5 g/t Au. For the notes related to the December 31, 2018 resource estimate, please consult the March 5, 2019 press release available on the Company’s website. For the notes related to the June 30, 2019 resource estimate, please consult the below section entitles Le Plaque Resource Modelling. The Ity Mine Mineral Resource is inclusive of Ity Mine depletion since December 31, 2018. The updated Mineral Resource is current as of December 31, 2018.

Since drilling began in Q1-2018, a strong focus has been placed on understanding the potential of the wider Le Plaque area as only 413 holes were used for resource delineation out of the 1,361 holes drilled in the wider area.

In addition to the Le Plaque resource definition program, a total of 948 Air Core (“AC”) holes totalling 39,440 meters were drilled on a more regional scale on the northern part of the Floleu license on a 200-meter by 50-meter northwest-southeast oriented grid. This reconnaissance drilling outlined that Le Plaque represents only 20% of the large Northern Floleu anomalic area where at least 7 other targets were identified, as shown in Figure 2 below. Drilling on these targets is expected to continue in H2-2019 with a strong focus in 2020 to delineate maiden resources.

Figure 2 - Nearby Le Plaque Targets

ABOUT THE LE PLAQUE DEPOSIT
Due to the significance of the Le Plaque high-grade discovery for the Ity mine, most of the exploration efforts on this asset since March 2018 focused on extending and delineating the discovered mineralization.

In light of the high grade, and sometimes very high grade, nature of the mineralization and its related structural complexity, including numerous mineralized intervals, an intensive RC/DD in-fill drill program was completed based on 25-meter spaced sections with 33-meter nominal spacing, generally with an angle of 50° towards the SE (N135°E), except for the Plaque Main area where drilling was orientated towards the SW (N225°E). The Le Plaque South area was also partly covered by a 25-meter by 25-meter AC grid to quickly define very shallow and rich oxide mineralization. The drilling program was very successful as over 85% of the drilled RC and DD holes encountered at least one interval of mineralization of 0.5g/t Au with a minimum true width of more than 2 meters.

A sensitivity analysis performed at a gold price of $1,250/oz demonstrates the robustness of the Le Plaque resources model due to its high-grade mineralization, as shown in Table 3 below.

Table 3: Le Plaque June 2019 Mineral Resource Estimate

No Measure resources have been estimated. 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 $1,500/oz Pit Shell and for sensitivity purpose by MII $1,250/oz pit shell and based on a cutoff of 0.5 g/t Au.

The Le Plaque deposit is now composed of 3 zones (Le Plaque Main, Epsilon and Le Plaque South), as shown in Figure 3 below.
 Figure 3 - Le Plaque Drill Map and Selected Intercepts (true width - grade) Per Area

The updated Le Plaque resource covers an area at least 1,200 meters long by 200 meters wide for the contact between hostrocks and granodiorite (the Le Plaque Main and Epsilon areas), and an area of at least 600 meters long by 300 meters wide for Le Plaque South area, within the granodiorite. Le Plaque Main area remains open at depth and towards the north/northwest, the Epsilon area at depth and towards the north/northeast, and Le Plaque South area at depth and towards the west, south and east.

Selected best intercepts since March 2018 include (true width uncapped):

• Le Plaque Main area:
  • FL18-709: 11.7m at 106g/t Au, including 2.0m at 620g/t Au (company-wide record intercept)
  • FL18-712: 7.8m at 8.25g/t Au, including 1.0m at 52.1g/t Au
  • FL18-724: 9.8m at 7.43g/t Au, including 2.0m at 26.5g/t Au, and 5.9m at 14.4g/t Au, including 1m at 69.0g/t Au
  • FL18-752: 3.2m at 32.7g/t Au, including 1.2m at 82.5g/t Au
  • FL18-776: 8.9m at 40.3g/t Au, including 2.3m at 151g/t Au
  • FL18-796: 5.2m at 44.8g/t Au, including 1.0m at 213g/t Au
  • FL18-800: 5.2m at 10.5g/t Au, including 1.0m at 49.7g/t Au
  • FL19-940: 3.8m at 25.5g/t Au, including 1.8m at 52.8g/t Au

• Epsilon area:
  • FL18-726: 3.8m at 19.7g/t Au, including 1.4m at 51.3g/t Au
  • FL18-739: 16.4m at 25.0g/t Au, including 9.2m at 42.5g/t Au, and 6.8m at 10.2g/t Au, including 2.4m at 26.7g/t Au
  • FL18-749: 10.4m at 6.19g/t Au, including 1.7m at 23.1g/t Au
  • FL18-750: 6.9m at 22.7g/t Au, including 1.7m at 79.2g/t Au
  • FL18-778: 4.6m at 18.3g/t Au, including 1.7m at 47.0g/t Au
  • FL18-780: 10.3m at 24.8g/t Au, including 0.9m at 166g/t Au and 1.8m at 48.3g/t Au
  • FL18-802: 5.3m at 28.7g/t Au, including 2.7m at 56.4g/t Au
  • FL18-803: 4.3m at 17.9g/t Au, including 0.9m at 68.0g/t Au
  • FL18-824: 6.3m at 8.88g/t Au, including 1.5m at 23.0g/t Au
  • FL18-832 : 7.7m at 20.8g/t Au, including 2.7m at 57.2g/t Au
  • FL18-833: 3.7m at 12.9g/t Au and 5.9m at 49.6g/t Au, including 4.3m at 67.8g/t Au
  • FL18-846: 7.2m at 15.0g/t Au, including 1.9m at 49.7g/t Au, and 16.8m at 6.13g/t Au, including 1.0m at 57.0g/t Au
  • FL18-849: 25m at 3.64g/t Au, including 1.7m at 22.1g/t Au
  • FL18-851: 15.5m at 16.5g/t Au, including 4.3m at 55.7g/t Au
  • FL18-853: 5.2m at 11.7g/t Au, including 0.9m at 48.8g/t Au
  • FL18-854: 3.5m at 19.3g/t Au, including 0.9m at 71.7g/t Au
  • FL18-857: 16m at 7.93g/t Au, including 2.9m at 21.7g/t Au
  • FL18-860: 7.6m at 13.2g/t Au, including 4.4m at 20.5g/t Au, and 2.8m at 20.4g/t Au
  • FL18-871: 5.2m at 11.4g/t Au, including 3.9m at 14.9g/t Au, and 4.8m at 16.0g/t Au, including 1.1m at 61.3g/t Au
  • FL18-872: 7.8m at 22.5g/t Au, including 1.7m at 86.6g/t Au
  • FL18-886: 3.5m at 38.6g/t Au, including 2.2m at 61.4g/t Au
  • FL18-893: 6.5m at 8.58g/t Au, including 0.9m at 56.4g/t Au, and 5.9m at 10.5g/t Au, including 1.5m at 34.4g/t Au
  • FL19-897: 5.6m at 12.3g/t Au, including 1.1m at 52.1g/t Au, and 5.1m at 43.9g/t Au, including 3.2m at 70.5g/t Au
  • FL19-912: 2.4m at 37.4g/t Au, including 0.9m at 100g/t Au
  • FL19-919: 13.1m at 12.2g/t Au, including 4.1m at 24.3g/t Au and 2.1m at 19.6g/t Au
  • FL19-958: 4.3m at 18.7g/t Au, including 2.2m at 34.6g/t Au
  • FL19-995: 2.9m at 41.4g/t Au, including 1.0m at 114g/t Au

• Le Plaque South area:
  • FL18-731: 8.2m at 9.64g/t Au, including 5.2m at 14.5g/t Au
  • FL18-823: 7.8m at 6.57g/t Au, including 0.9m at 44.7g/t Au
  • FL19-941: 16.4m at 9.07g/t Au, including 2.2m at 52.6g/t Au
  • FL19-963: 14.1m at 8.11g/t Au, including 0.7m at 121g/t Au
  • FL19-967: 25.7m at 10.9g/t Au, including 5.4m at 38.0g/t Au
  • FL19-978: 5.3m at 9.96g/t Au, including 1.0m at 41.5g/t Au

The geology of Le Plaque consists of a granodiorite batholith intruded into a sequence of Birimian meta-volcano-sediments, including dominantly meta-sediments (impure marbles, metasiltstones and sandstones) to the west, and a belt of mafic metavolcanics to the east. Several generations of diorite and microdiorite bodies of variable thickness occur within the metasediments as sheeted sills and dykes, including some which are cutting through or bordering the granodiorite. The metasediments and magmatic rocks have been affected by skarn alteration forming exoskarn and endoskarn, although this event appears not associated with gold, contrary to other Ity style mineralization, and the mineral paragenesis bears no significant copper.

The mineralization of Le Plaque is broadly associated with few meters-thick ductile and brittle-ductile shears with quartz veining, silica-sericite alteration and locally massive sulfidic seams (pyrite, with subordinate sphalerite, minor chalcopyrite and local trace of galena and pyrrhotite). There is no visible gold on core, even within the highest-grade intercepts, and almost no arsenopyrite. The presence of sphalerite, strong silicification and quartz veining usually correlates very well with the best grades. 

The anastomosed shearing network is usually well developed in the outer shell of the granodiorite, within the granodiorite and diorite units, and to a lesser extent within the skarn host rocks themselves.

The Le Plaque Main mineralization follows a west-northwest to east-southeast trending and moderately north-northeast-dipping contact of the granodiorite with the skarn host rocks and is partly hosted within a few 10 meter thick diorite intercalation thickening toward the west. As shown in Figure 4 below, the Epsilon mineralization occurs along a northeast-southwest to north-northeast to south-southwest trending and steeply west-northwest dipping contact of the granodiorite. The mineralization is mostly hosted within the granodiorite, except for the central sector where it straddles the contact and penetrates the skarn units.

Figure 4 - Section A - Epsilon Area

As shown in Figure 5 below, the Le Plaque South mineralization is associated with a set of en-echelon north-northeast-trending, steeply west-northwest-dipping shearing structures entirely hosted within the granodiorite, except for few meters-thick microdioritic dykes.

Oxidation profile varies from 30 meters on the granodiorite (Le Plaque South) up to 75 meters in skarn facies (average 50 meters on Le Plaque Main and Epsilon).

Figure 5 - Section B Through the Le Plaque Main and Le Plaque South Areas

NEXT STEPS

• Due to the success achieved with the H1-2019 extension and resource drilling campaign, and as the Le Plaque deposit remaining open at depth and in various directions, a follow-up 20,000-meter drilling campaign is expected to begin after the rainy season with the aim of further resource delineation.
• Further drilling is also expected to continue in H2-2019 and into 2020 on the new targets identified in the large Northern Floleu license anomalic area.
• A Le Plaque resource update is expected to be published by year-end.  
• Additional metallurgical and geotechnical tests are already underway, with a maiden Le Plaque reserve expected to be published ahead of the year-end statement in late Q4-2019 or Q1-2020.
• Environmental and Social Impact Assessment (“ESIA”) studies were initiated in mid-2018 and are expected to be completed later this year.

LE PLAQUE RESOURCE MODELLING

The statistical analysis, geological modelling and resource estimation were prepared by Kevin Harris, CPG. Mr. Harris is Endeavour Mining's V.P. Resource Manager and a Qualified Person as defined by NI 43-101.

The Le Plaque resource model was developed in Geovia’s Surpac software. A total of 30 mineralized zones were defined from the current drilling data and geologic interpretations across La Plaque.  The gold assays from the drill holes were composited to 1.0 meter intervals within the mineralized wireframes and capped at from 10 to 40 g/t Au based on the statistics of each mineralized zone.  Spatial analysis of the gold distribution within the mineralized zone using variograms indicated a good continuity of the grades along strike and down dip of the mineralized zones and were used to establish ordinary kriging parameters.

The density was measured in 2,224 core samples within the various rock types then averaged within the model by the weathered zones. The laterite density is 1.5, the saprolite is 1.4, the transition is 2.0, and the fresh rock is 2.8.

The gold grade was estimated with the ordinary kriging method constrained within the mineralized domains.  The grade was estimated in multiple passes to define the higher confidence areas and extend the grade to the interpreted mineralized zone extents.  The grade estimation was validated with visual analysis by comparison with the drilling data on sections, comparing with inverse distance squared estimation, and with swath plots comparing the block grades with the composites.

The mineralized domains were classified as indicated and inferred resource classifications depending on the sample spacing, number samples, confidence in mineralized zone continuity, and geostatistical analysis.  Indicated classification was generally applied to blocks within the mineralized zoned defined by a minimum of seven samples from at least three drill holes with a 45-meter search.  Inferred classification is defined by a minimum of three samples within a 75-meter search from two drill holes.

The resource was constrained by a $1,500 and a $1,250/oz pit shell and 0.50 g/t cut-off. The Whittle pit shell optimization assumed a base mining cost of $3.00 per tonne, and an adjusted ore mining cost of $3/tonne for oxide, $3.30/tonne for transition, and $3.60/tonne for fresh rock, mining recovery of 95%, mining dilution of 20%, pit slope of 40^o, gold recovery of 90% in oxide, transition and fresh rock, and processing and G&A cost of $20.00 per tonne.

ASSAYS AND QUALITY ASSURANCE/QUALITY CONTROL / DRILLING AND ASSAY PROCEDURES

The RC and AC drill program samples were collected on a 1-meter interval using dual tube, a percussion hammer. The material passes through a cyclone which is thoroughly cleaned after every sample by flushing the hole. Samples were split at the drill site using a 3-tier riffle splitter with both bulk and laboratory sample weights and moisture recorded. Representative samples for each interval were collected with a spear, sieved into chip trays and retained for reference.

Drill core (PQ, HQ and NQ size) samples are selected by Endeavour geologists and sawn in half with a diamond blade at the project site. Half of the core is retained at the site for reference purposes. Sample intervals are generally 1 meter in length.

All samples are transported by road to Bureau Veritas in Abidjan or to SGS. Each laboratory sample is secured in poly-woven bags ensuring that there is a clear record of the chain of custody. On arrival samples are weighed and crushed to 2mm (70% passing), pulverize entire sample to 75μm (85% passing). Samples are analyzed for gold using standard fire assay technique with a 50-gram charge and an Atomic Absorption (AA) finish. Blanks, field duplicates and certified reference material (CRM’s) are inserted by Endeavour geologists in the sample sequence for quality control and to ensure there are a suite of QC samples in each fire assay batch.

The sampling and assaying are monitored through the implementation of a quality assurance – quality control (QA-QC) program. This QA-QC program was audited by International consultant, independent from Endeavour Mining, in 2019 and consequently designed to follow industry best practices.

Full drill results are available by clicking

QUALIFIED PERSONS

The scientific and technical content of this news release has been reviewed, verified and compiled by Gérard de Hert, EurGeol, Senior VP Exploration for Endeavour Mining. Gérard de Hert 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"). The resource estimation was completed by Kevin Harris, CPG, VP Resources for Endeavour Mining and "Qualified Person" as defined by National Instrument 43-101.

CONTACT INFORMATION

ABOUT ENDEAVOUR MINING CORPORATION

Endeavour Mining is a TSX listed intermediate African gold producer with a solid track record of operational excellence, project development and exploration in the highly prospective Birimian greenstone belt in West Africa. Endeavour is focused on offering both near-term and long-term growth opportunities with its project pipeline and its exploration strategy, while generating immediate cash flow from its operations.

Endeavour operates 4 mines across Côte d’Ivoire (Agbaou and Ity) and Burkina Faso (Houndé, Karma) which are expected to produce 615-695koz in 2019 at an AISC of $760-810/oz. 

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

Corporate Office: 5 Young St, Kensington, London W8 5EH, UK   

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. AISC, all-in sustaining costs at the mine level, cash costs, operating EBITDA, all-in sustaining margin, free cash flow, net free cash flow, free cash flow per share, net debt, and adjusted earnings are non-GAAP financial performance measures with no standard meaning under IFRS, further discussed in the section Non-GAAP Measures in the most recently filed Management Discussion and Analysis.

Attachments

• Figure 1 - Greater Ity General Map with Le Plaque Location
• Figure 2 - Nearby Le Plaque Targets
• Figure 3 - Le Plaque Drill Map and Selected Intercepts (true width - grade) Per Area
• Figure 4 - Section A - Epsilon Area
• Figure 5 - Section B Through the Le Plaque Main and Le Plaque South Areas
• Le Plaque Dill Intercepts
• View News Release in PDF Format