Try our mobile app

Published: 2022-08-04 17:00:47 ET
<<<  go to MUX company page
EX-99.1 2 tm2222612d1_ex99-1.htm EXHIBIT 99.1

 

Exhibit 99.1

 

 

McEwen Copper

Los Azules Progress Report #4

Long intercepts with good grades

 

222.0 m of 0.95% Cu including 44.0 m of 1.38% Cu (AZ22158)

238.0 m of 0.58% Cu including 10.0 m of 1.10% Cu (AZ22161)

194.0 m of 0.56% Cu including 8.0 m of 1.04% Cu (AZ22163)

 

TORONTO, August 4, 2022 - McEwen Copper Inc., a subsidiary of McEwen Mining Inc. (NYSE: MUX) (TSX: MUX), is pleased to report the latest assay results from its Los Azules project, which continues to deliver long intercepts of good grades.

 

The drill program underway has three important objectives:

Improve confidence in the resource by converting Inferred mineral resources to the Indicated category;

Accelerate project advancement with metallurgical, hydrological and geotechnical drilling and

Test the limits of the depth extension of the higher-grade mineralization.

 

Results from this drilling program will be used to update the 2017 Los Azules PEA (Preliminary Economic Assessment). The updated version will be released in Q1, 2023.

 

The 2017 PEA was calculated using prices of $3/lb copper, $1,300/oz gold and $17/oz silver price. It projected robust economics, driven by large operating margins, large annual production, a short payback period and long mine life (link to the report: http://www.mcewenmining.com/files/technical_reports/los_azules/LosAzulesPEA_Rev0_20171016.pdf). Drilling has halted for the winter and will resume in October when spring arrives in Argentina.

 

Earlier this year, Mining Intelligence ranked Los Azules as one of the world’s top five largest undeveloped porphyry copper deposits that is not already owned by a major mining company.

 

The opportunity to expand the deposit at depth remains open for further testing. While the median depth of drill holes within the Los Azules resource database is 175 meters (m), it is not uncommon for porphyry copper mineralization to extend well beyond a kilometer or more of depth. Numerous drill holes have encountered strong copper grades below the 2017 PEA pit bottom. Only three holes have been drilled to a depth of a kilometer and all encountered mineralization.

 

The highest-grade mineral domains at Los Azules are clearly the hydrothermal and magmatic breccias and late-stage quartz veins which can extend kilometres to depth. There are numerous examples of such deposits in Argentina and Chile. The most recent is Filo Mining’s spectacular assay results of earlier this year. The Filo deposit is 300 kilometres north of Los Azules, also in the San Juan province, Argentina.

 

The deepest occurrence of a breccia at Los Azules is at a hole depth of some 810 m in drill hole AZ1299 and deepest occurrence of late-stage quartz veins is found at 990 m down the same hole.

 

A dedicated exploration program associated with higher grade domains at Los Azules has not yet been conducted. Most holes drilled to date are vertical and intersect the breccias at very low angles. Improving our understanding of the nature and distribution of the highest-grade mineral zones at Los Azules is a priority for the upcoming drilling seasons.

 

The most recent drill results are presented below in the cross-section Figures 1 to 4. These display the current inclined and historic vertical holes, with histograms of total copper content along their length, overlayed on a simplified interpretation of overburden, leached, enriched and primary mineral zones, and the 30-year pit shell (shown by green line), as defined by the 2017 PEA.

McEwen Mining Inc.Page 1 

 

 

 

Section 30-30', shown in Figure 1, includes hole AZ22158, with an attractive intercept of 222.0 m grading 0.95% Cu, and including an interval of 44.0 m grading 1.38% Cu. Partial results were reported in the Los Azules Progress Report #3 published on June 23, 2022. Hole AZ22166 was stopped at the arrival of winter and will be completed in spring.

 

Figure 1 – Cross-section 30-30’

 

 

 

Section 36-36’, shown in Figure 2, received eight new drill holes during the recent campaign. The final intercept reported was hole AZ22162, which targeted the gap between hole AZ22138 (522.1 m grading 0.42% Cu) and AZ22139.

 

Hole AZ22162 returned 348.0 m grading 0.28% Cu, while also ending in enriched mineralization. It appears to correlate well with historic hole AZ0838 (188.3 m grading 0.27% Cu).

McEwen Mining Inc.Page 2 

 

 

 

Figure 2 – Cross-section 36-36’

 

 

 

Cross Section 44-44' shown in Figure 3 presents hole AZ22163 (194.0 m grading 0.56% Cu). AZ22163 includes 8.0 m of high-grade 1.04% Cu and supports 146.0 m of high-grade 1.10% Cu reported in historic hole AZ0620. Hole AZ22167 (80.4 m grading 0.21% Cu) results are as expected and similar to the historic hole LA0402.

 

Figure 3 - Cross-section 44-44’

 

 

McEwen Mining Inc.Page 3 

 

 

 

Cross-section 48-48' shown in Figure 4, profiles three new holes. Hole AZ22149 (296.4 m grading 0.55% Cu including 54 m of 1.38% Cu), drilled just west of the center of the section, was released in our June 23 exploration update. Hole AZ22161, drilled east of the center of the section, with 238.0 m grading 0.58% Cu and including 10 m of 1.10% Cu, supports historic intercepts in adjacent holes AZ1060A (221.0 m grading 0.53% Cu) and AZ18136 (194.0 m grading 0.43% Cu), all below the 30-year pit shell, indicating significant potential for mineralization at depth.

 

Holes AZ22147 and AZ22165 were drilled off the west and east flanks to delimit margins of the deposit and did not encounter significant mineralization.

 

Figure 4 - Cross-section 48-48’

 

 

McEwen Mining Inc.Page 4 

 

 

 

Figure 5 - Locations of the cross-sections on the plan of the deposit

 

 

 

The Los Azules deposit is sequentially sub-divided into 50 m cross sections beginning at the southeast end of the deposit and progressing to the northwest. Section 36-36’ is approximately the mid-section of the deposit. As a matter of cross-referencing results presented in the Los Azules Progress Report #3 published on June 23, 2022, note that Section 36-36’ was previously identified as Section A-A’ and Section 48-48’ as Section C-C’. Section 40-40’ identifies with Section B-B’ and was not included in this release as no new results have been added there.

 

Drilling resumes in October, and the plan is to complete 45,500 m.

 

Link to Drilling Results and Hole Collar Locations and Lengths for January to May 2022 at Los Azules: https://www.mcewenmining.com/files/doc_news/archive/2022/202208_LosAzules/2022_08_Los_Azules_Update_4.xlsx (alternatively see Tables 1 and 2 at the end of this press release).

 

Technical Information

 

The technical content of this news release has been reviewed and approved by Stephen McGibbon, P.Geo, SVP Exploration of McEwen Mining and a Qualified Person as defined by NI 43-101.

McEwen Mining Inc.Page 5 

 

 

 

All samples were collected in accordance with generally accepted industry standards. Drill core samples usually taken at 2 m intervals are split and submitted to Alex Stewart International laboratory in Mendoza, Argentina for the following assays: gold determination using fire assay fusion and an atomic absorption spectroscopy finish (Au4-30); a 39 multi-element suite using ICP-OES analysis (ICP-AR 39); copper content determination using a sequential copper analysis (Cu-Sequential). An additional 19-element analysis (ICP-ORE) was performed for samples with high sulfide content.

 

The Company carries out a Quality Assurance / Quality Control program consistent with NI 43-101 and industry best practices utilising a combination of standards and blanks approximately one in every 25 samples. Results are monitored as the final certificates are received and any re-assay requests are sent back immediately. Pulp and prep duplicate sample analyses are also taken as part of the QAQC process. Approximately 5% of sample pulps are sent to a secondary laboratory for check assays. In addition, the assay lab performs its own internal QAQC checks with results available in the certificates for review by the Company.

 

Table 1 – Drill Results January-May 2022 at Los Azules

 

Hole-ID   Section   Predominant
Mineral Zone
  From
(m)
  

To

(m)

   Length
(m)
  

Cu

(%)

  

Au

(g/t)

  

Ag

(g/t)

   Comment
AZ22137A   36   Total  133.0   557.3   424.3   0.47   0.027   0.008    
incl       Enriched  133.0   342.0   209.0   0.49   0.028   0.016    
and       Primary  342.0   557.3   215.3   0.44   0.026   0.001   incl. 8m of 1.00% Cu in Primary
AZ22138   36   Total  138.0   660.1   522.1   0.42   0.064   1.883    
incl       Enriched  138.0   348.0   210.0   0.60   0.064   2.180   incl. 28m of 0.87% Cu in Enriched
and       Primary  348.0   660.1   312.1   0.30   0.065   1.683    
AZ22139   36   Total  114.5   282.6   168.2   0.08   0.060   1.447    
incl       Enriched  206.5   282.6   76.1   0.12   0.032   1.164    
AZ22140   36   Total  117.4   342.8   225.4   0.16   0.030   1.117    
incl       Enriched  117.4   314.0   196.6   0.16   0.032   1.173    
and       Primary  314.0   342.8   28.8   0.16   0.019   0.732    
AZ22141   40   Total  183.1   551.0   367.9   0.50   0.069   1.535    
incl       Enriched  183.1   360.0   176.9   0.50   0.044   1.437    
and       Primary  360.0   551.0   191.0   0.50   0.092   1.625    
AZ22142   36   Total  92.0   511.1   419.1   0.79   0.152   3.508   incl 32m of 1.11% Cu &
incl       Enriched  92.0   278.0   186.0   0.93   0.095   3.544   104m of 1.00% Cu in Enriched
and       Primary  278.0   511.1   233.1   0.67   0.198   3.479   46m of 1.59% Cu in Primary
AZ22143   36   Total  92.5   403.0   310.5   0.20   0.015   0.880    
incl       Enriched  92.5   266.0   173.5   0.22   0.016   0.985    
and       Primary  266.0   403.0   137.0   0.18   0.014   0.747    
AZ22144   36   Total  58.0   506.6   448.6   0.30   0.02   0.84    
incl       Enriched  58.0   204.0   146.0   0.31   0.01   0.52    
and       Primary  204.0   506.6   302.6   0.29   0.02   1.00   incl 104.6m of 0.48% Cu
AZ22145   40   Total  76.0   257.0   181.0   0.18   0.02   1.90    
incl       Enriched  76.0   194.0   118.0   0.16   0.03   2.25    
and       Primary  194.0   257.0   63.0   0.21   0.01   1.26    
AZ22146   40   Total  91.0   421.5   330.5   0.83   0.11   2.30    
incl       Enriched  91.0   394.0   303.0   0.86   0.11   2.26   incl 103.4m of 1.31% Cu
and       Primary  394.0   421.5   27.5   0.50   0.10   2.76    
AZ22147   48   Total  60.0   240.8   180.8   0.03   0.02   0.50    
incl       Enriched  60.0   67.0   7.0   0.10   0.08   1.27    
AZ22148   40   Total  76.0   315.0   239.0   0.26   0.02   1.01    
incl       Enriched  76.0   212.0   136.0   0.33   0.02   0.85    
and       Primary  212.0   315.0   103.0   0.16   0.02   1.23    

McEwen Mining Inc.Page 6 

 

 

 

Hole-ID   Section   Predominant
Mineral Zone
  From
(m)
  

To

(m)

   Length
(m)
  

Cu

(%)

  

Au

(g/t)

  

Ag

(g/t)

   Comment
AZ22149   48   Total  131.6   428.0   296.4   0.55   0.04   1.62    
incl       Enriched  131.6   278.0   146.4   0.34   0.02   0.32    
and       Primary  278.0   428.0   150.0   0.76   0.06   2.91   incl 54m of 1.38% Cu from 376m
AZ22150   44   Total  78.0   257.4   179.4   0.14   0.01   0.53    
incl       Enriched  78.0   126.0   48.0   0.04   0.01   0.25    
and       Primary  126.0   257.4   131.4   0.17   0.01   0.63    
AZ22158   30   Enriched  72.0   294.0   222.0   0.95   0.09   1.57   incl 44m of 1.38% Cu from 144m
and       Primary  294.0   300.0   6.0   0.34   0.05   0.43    
AZ22161   48   Enriched  116.0   354.0   238.0   0.58   0.07   1.19   incl 10m of 1.10% Cu from 156m
AZ22162   36   Enriched  102.0   450.0   348.0   0.28   0.40   1.13   incl 2m of 0.86% Cu from 232m
AZ22163   44   Enriched  92.0   286.0   194.0   0.56   0.04   0.68   incl 8m of 1.04% Cu from 98m
AZ22164   38   Leached  18.0   242.0   224.0   0.04   0.02   1.32    
AZ22165   48   Leached  24.5   200.0   175.5   0.04   0.04   1.27    
AZ22166   30   Enriched  82.7   199.6   116.9   0.13   0.02   0.81   incl 53.6m of 0.25% Cu from 146m
AZ22167   44   Enriched  72   152.4   80.4   0.21   0.02   0.78   incl 54.4m of 0.25% Cu from 98m

 

Table 2 - Hole Collar Locations and Lengths for January-May 2022 Drill Results at Los Azules

 

HOLE-ID  Azimuth   Dip   Length   Loc X   Loc Y   Loc Z 
AZ22137A   250    -70    557.3    2383289    6559336    3667 
AZ22138   250    -78    660.1    2383569    6559450    3676 
AZ22139   70    -79    282.6    2383725    6559494    3719 
AZ22140   160    -76    342.8    2383687    6559463    3701 
AZ22141   250    -78    551.0    2383530    6559636    3669 
AZ22142   70    -65    511.1    2383286    6559334    3667 
AZ22143   250    -70    403.0    2382768    6559131    3723 
AZ22144   250    -70    506.6    2382889    6559204    3688 
AZ22145   250    -73    257.0    2382912    6559411    3628 
AZ22146   250    -75    422.0    2383406    6559591    3644 
AZ22147   250    -68    241.0    2382558    6559708    3642 
AZ22148   250    -75    315.0    2383106    6559482    3647 
AZ22149   70    -77    428.0    2382879    6559875    3618 
AZ22150   70    -82    257.4    2382670    6559536    3661 
AZ22158   250    -65    300.0    2383561    6559115    3627 
AZ22161   250    -81    354.0    2383575    6559120    3658 
AZ22162   250    -70    450.0    2383442    6560030    3641 
AZ22163   73    -70    286.0    2383725    6559494    3719 
AZ22164   70    -68    242.0    2383429    6559812    3648 
AZ22165   70    -71    200.0    2383733    6559603    3726 
AZ22166   250    -70    199.6    2383652    6560106    3672 
AZ22167   70    -80    152.4    2383727    6559175    3675 

 

Coordinates listed in Table 2 based on Gauss Kruger - Campo Inchauspe Zone 2 

 

McEwen Mining Inc.Page 7 

 

 

 

 

WEBSITE

www.mcewenmining.com

 

CONTACT INFORMATION

 

150 King Street West

Suite 2800, P.O. Box 24

Toronto, ON, Canada

M5H 1J9

 

Investor Relations:

(866)-441-0690 Toll-Free

(647)-258-0395

 

Mihaela Iancu ext. 320

info@mcewenmining.com 

SOCIAL MEDIA 

 
  McEwen Mining 
Facebook:  facebook.com/mcewenmining 
LinkedIn:  linkedin.com/company/mcewen-mining-inc- 
Twitter:  twitter.com/mcewenmining 
Instagram:  instagram.com/mcewenmining 
 

 

McEwen Copper 

Facebook:  facebook.com/mcewencopper 
LinkedIn:  linkedin.com/company/mcewencopper 
Twitter:  twitter.com/mcewencopper 
Instagram:  instagram.com/mcewencopper  
 

 

Rob McEwen 

Facebook:  facebook.com/mcewenrob  
LinkedIn:  linkedin.com/in/robert-mcewen-646ab24 
Twitter:  twitter.com/robmcewenmux 

 

McEwen Mining Inc.Page 8