Resource

2025 CUSI Mineral Resource Statement

Highlights of the Cusi Project underground Mineral Resource Estimate are as follows:

  • Combined Measured and Indicated Mineral Resources are estimated at 4.89 Mt grading 206 g/t silver, 0.15 g/t gold, 0.73% lead, and 0.86% zinc (262 g/t AgEq). The Mineral Resource Estimate includes Measured Mineral Resources of 6.1 Moz of silver, 1.8 koz of gold, 5.6 Mlbs of lead, and 6.3 Mlbs of zinc (6.7 Moz of AgEq) and Indicated Mineral Resources of 26.3 Moz of silver, 22.2 koz of gold, 72.7 Mlbs of lead, and 86.5 Mlbs of zinc (34.4 Moz of AgEq).
  • Inferred Mineral Resources are estimated at 4.07 Mt grading 172 g/t silver, 0.17 g/t gold, 0.89% lead, and 1.20% zinc (243 g/t AgEq). The Mineral Resource Estimate includes Inferred Mineral Resources of 22.5 Moz of silver, 22.2 koz of gold, 79.5 Mlbs of lead, and 107.5 Mlbs of zinc (31.7 Moz of AgEq).

Table 1: Cusi Project Underground Mineral Resource Estimate, October 20, 2025

Resource Class Mass Average Grade Material Content
Ag Au Pb Zn AgEq Ag Au Pb Zn AgEq
Mt g/t g/t % % g/t koz koz Mlb Mlb koz
Measured 0.69 277 0.08 0.37 0.42 305 6,114 1.8 5.6 6.3 6,725
Indicated 4.21 195 0.16 0.78 0.93 255 26,330 22.2 72.7 86.5 34,433
M + I 4.89 206 0.15 0.73 0.86 262 32,443 24 78.3 92.8 41,157
Inferred 4.07 172 0.17 0.89 1.2 243 22,479 22.2 79.5 107.5 31,753

Cusi Project Mineral Resource Estimate Notes:

  1. The mineral resource was estimated by Ben Eggers, MAIG, P.Geo. of SGS Geological Services, an independent Qualified Person as defined by NI 43-101. Eggers conducted a site visit to the Cusi Property on September 22-23, 2025. The mineral resource was peer reviewed by Allan Armitage, Ph.D., P.Geo. of SGS Geological Services, an independent Qualified Person as defined by NI 43-101.
  2. The classification of the Mineral Resource Estimate into Indicated and Inferred mineral resources is consistent with current 2014 CIM Definition Standards for Mineral Resources and Mineral Reserves. The effective date of the Cusi Project Mineral Resource Estimate (MRE) is October 20, 2025. This is the close out date for the final mineral resource drilling database.
  3. All figures are rounded to reflect the relative accuracy of the estimate and numbers may not add due to rounding.
  4. All mineral resources are presented undiluted and in situ, constrained by continuous 3D wireframe models (considered mineable shapes), and are considered to have reasonable prospects for eventual economic extraction. The mineral resource is exclusive of mined out material.
  5. Mineral resources are not mineral reserves. Mineral resources which are not mineral reserves, do not have demonstrated economic viability. An Inferred Mineral Resource has a lower level of confidence than that applying to an Indicated or Measured Mineral Resource and must not be converted to a Mineral Reserve. It is reasonably expected that the majority of Inferred Mineral Resources could be upgraded to Indicated or Measured Mineral Resources with continued exploration.
  6. The Cusi Project MRE is based on a validated database which includes data from 2,052 surface and underground drillholes totalling 360,237 m completed between 2006 and October 2025 and 21,522 channels totalling 48,786 m completed between 2013 and 2023. The resource database totals 105,585 assay intervals representing 119,756 m of drillhole data and 71,605 assay intervals representing 48,783 m of channel data.
  7. The mineral resource estimate is based on 63 three-dimensional (“3D”) resource models representing epithermal veins which comprise the Cusi vein systems. 3D models of mined out areas were used to exclude mined out material from the current MRE.
  8. Grades for Ag, Au, Pb, and Zn are estimated for each mineralization domain using 1.5 m capped composites assigned to that domain. To generate grade within the blocks, the inverse distance squared (ID2) interpolation method was used for all domains.
  9. An average density value of 2.75 g/cm3 was assigned to all domains based on a database of 244 samples.
  10. It is envisioned that the Cusi Project deposits may be mined using underground mining methods. Mineral resources are reported at a base case cut-off grade of 120 g/t AgEq. The mineral resource grade blocks were quantified above the base case cut-off grade, below surface, within the constraining mineralized wireframes, and exclusive of mined out material.
  11. The underground base case cut-off grade of 120 g/t AgEq considers metal prices of US$30/oz Ag, US$2400/oz Au, US$1.00/lb Pb, and US$1.35/lb Zn and metal recoveries of 90% for Ag, 50% for Au, 90% for Pb, and 60% for Zn.
  12. The underground base case cut-off grade of 120 g/t AgEq considers a mining cost of US$60.00/t rock and a processing, treatment and refining, transportation and G&A cost of US$35.00/t mineralized material.
  13. The estimate of Mineral Resources may be materially affected by environmental, permitting, legal, title, taxation, socio-political, marketing, or other relevant issues.

Table 2: Cusi Project Underground Mineral Resource Estimate by Area, October 20, 2025

Area Resource Class Mass Average Grade Material Content
Ag Au Pb Zn AgEq Ag Au Pb Zn AgEq
Mt g/t g/t % % g/t koz koz Mlb Mlb koz
San Juan Indicated 0.2 232 0.21 0.17 0.2 259 1,199 1.1 0.6 0.7 1,338
Inferred 0.1 295 0.07 0.29 0.51 324 1,156 0.3 0.8 1.4 1,267
Promontorio West Indicated 1.0 208 0.1 0.43 0.58 244 6,893 3.4 9.8 13.1 8,078
Inferred 0.4 199 0.19 0.78 0.79 257 2,592 2.5 7 7.1 3,342
Promontorio East Measured 0.5 285 0.08 0.3 0.36 309 4,824 1.3 3.4 4.1 5,229
Indicated 0.2 211 0.19 0.81 0.6 264 1,609 1.5 4.2 3.1 2,006
M + I 0.8 262 0.11 0.46 0.43 295 6,432 2.8 7.7 7.2 7,235
Inferred 0.2 231 0.32 0.86 0.83 301 1,520 2.1 3.9 3.8 1,987
Eduwiges Indicated 0.5 159 0.25 1.93 2.06 287 2,694 4.2 22.3 23.9 4,853
Inferred 0.2 92 0.18 1.94 2.39 224 694 1.4 10 12.4 1,697
San Miguel Indicated 1.3 193 0.15 0.83 1.11 258 8,065 6.2 23.9 31.7 10,786
Inferred 2.0 170 0.14 1.02 1.42 249 11,117 9.3 45.5 63.5 16,237
San Nicolas Indicated 0.8 196 0.17 0.41 0.43 233 4,798 4.2 6.9 7.2 5,684
Inferred 0.6 175 0.14 0.28 0.45 207 3,472 2.9 3.8 6.2 4,105
Santa Rosa de Lima Measured 0.2 251 0.09 0.6 0.62 291 1,290 0.5 2.1 2.2 1,496
Indicated 0.2 176 0.29 1.2 1.63 276 1,072 1.8 5 6.8 1,688
M + I 0.4 210 0.2 0.93 1.17 283 2,362 2.2 7.2 9 3,183
Inferred 0.5 133 0.27 0.86 1.34 216 1,928 3.8 8.5 13.3 3,118
Total Measured 0.7 277 0.08 0.37 0.42 305 6,114 1.8 5.6 6.3 6,725
Indicated 4.2 195 0.16 0.78 0.93 255 26,330 22.2 72.7 86.5 34,433
M + I 4.9 206 0.15 0.73 0.86 262 32,443 24 78.3 92.8 41,157
Inferred 4.1 172 0.17 0.89 1.2 243 22,479 22.2 79.5 107.5 31,753
  1. The underground base case cut-off grade of 120 g/t AgEq considers metal prices of US$30/oz Ag, US$2400/oz Au, US$1.00/lb Pb, and US$1.35/lb Zn, metal recoveries of 90% for Ag, 50% for Au, 90% for Pb, and 60% for Zn, a mining cost of US$60.00/t rock, and a processing, treatment and refining, transportation and G&A cost of US$35.00/t mineralized material.

Table 3: Cusi Project Mineral Resource Estimate Sensitivity Table, October 20, 2025

Resource Class Cut-off Grade (AgEq g/t) Mass Average Grade Material Content
Ag Au Pb Zn AgEq Ag Au Pb Zn AgEq
Mt g/t g/t % % g/t koz koz Mlb Mlb koz
Measured 80 g/t 0.9 232 0.07 0.34 0.38 257 6,668 2 6.7 7.5 7,388
90 g/t 0.8 244 0.07 0.35 0.39 269 6,531 1.9 6.4 7.2 7,222
100 g/t 0.8 254 0.07 0.35 0.4 281 6,397 1.9 6.1 6.9 7,064
120 g/t 0.7 277 0.08 0.37 0.42 305 6,114 1.8 5.6 6.3 6,725
150 g/t 0.6 312 0.09 0.4 0.45 342 5,643 1.6 4.9 5.5 6,188
200 g/t 0.4 375 0.11 0.45 0.49 409 4,860 1.4 4 4.3 5,299
250 g/t 0.3 445 0.13 0.49 0.53 483 4,132 1.2 3.2 3.4 4,484
300 g/t 0.2 512 0.14 0.53 0.57 553 3,571 1 2.5 2.7 3,858
Indicated 80 g/t 5.9 161 0.13 0.63 0.76 210 30,612 25.2 81.9 99.1 39,827
90 g/t 5.4 170 0.14 0.67 0.81 221 29,566 24.3 79.6 96.2 38,506
100 g/t 5 178 0.15 0.7 0.85 232 28,512 23.6 77.3 93 37,175
120 g/t 4.2 195 0.16 0.78 0.93 255 26,330 22.2 72.7 86.5 34,433
150 g/t 3.3 218 0.18 0.9 1.06 286 23,388 19.7 66.1 77.6 30,664
200 g/t 2.3 257 0.21 1.08 1.25 337 18,988 15.6 54.8 63.2 24,913
250 g/t 1.6 296 0.24 1.22 1.39 386 15,290 12.3 43.4 49.3 19,938
300 g/t 1.1 338 0.26 1.38 1.54 439 11,876 9.3 33.1 37 15,396
Inferred 80 g/t 5.7 143 0.14 0.72 1 201 26,266 26 90.9 126.1 37,065
90 g/t 5.3 150 0.15 0.76 1.04 211 25,377 25.1 88 121.2 35,787
100 g/t 4.8 157 0.16 0.8 1.1 222 24,424 24.2 85.4 116.8 34,469
120 g/t 4.1 172 0.17 0.89 1.2 243 22,479 22.2 79.5 107.5 31,753
150 g/t 3 199 0.2 1.05 1.38 282 19,192 18.9 69.7 91.1 27,135
200 g/t 1.9 246 0.24 1.36 1.67 347 14,786 14.4 56.2 69.1 20,924
250 g/t 1.4 277 0.27 1.57 1.87 393 12,252 12 47.6 56.8 17,358
300 g/t 1 310 0.31 1.76 2.03 437 9,965 9.8 38.8 44.8 14,061
  1. Underground mineral resources are reported at a base case cut-off grade of 120 g/t AgEq (highlighted). Values in this table reported above and below the base case cut-off grades should not be misconstrued with a Mineral Resource statement. The values are only presented to show the sensitivity of the block model estimate to the base case cut-off grade.
  2. All values are rounded to reflect the relative accuracy of the estimate and numbers may not add due to rounding.

Qualified Persons

The mineral resource was estimated by Ben Eggers, MAIG, P.Geo. of SGS Geological Services, an independent Qualified Person as defined by NI 43-101. Eggers conducted a site visit to the Cusi Property on September 22-23, 2025. The mineral resource was peer reviewed by Allan Armitage, Ph.D., P.Geo. of SGS Geological Services, an independent Qualified Person as defined by NI 43-101.