Santo Domingo Mineral Reserves & Resources

Santo Domingo Project Estimated Mineral Reserves as at November 14, 2018

Reserve Category Ore Grade  Contained Metal 
 Ore Cu  Fe Au Cu  Fe Conc. Au
(Mt) (%)  (%)  (g/t)  (Mlb)  (Mt)  (kOz) 
Proven Reserves 65.4 0.61 30.9 0.08 878.5 8.2 169.9
Probable Reserves 326.9 0.24 27.6 0.03 1,694.2 66.9 336.8

Total Reserves

392.3 0.30 28.2 0.04 2,572.7 75.1 506.7

NOTES: Santo Domingo Project Mineral Reserves shown on 100% basis (Capstone’s share is 70%). Carlos Guzman, FAusIMM, CMC, of NCL Ingeniería y Construcción SpA, is the independent Qualified Person responsible for the preparation of the Mineral Reserves estimate with an effective date of November 14, 2018. (1) Mineral Reserves are reported as constrained within Measured and Indicated pit designs and supported by a mine plan featuring variable throughput rates and cut-off optimization. The pit designs and mine plan were optimized using the following economic and technical parameters: metal prices of US$3.00/lb Cu, US$1,280/oz Au and US$100/dmt of FeO concentrate; the average recovery is 93.4% for Cu and 60.1% for Au, with magnetite concentrate recovery varying on a block-by-block basis; copper concentrate treatment charges of US$80/dmt, US$0.08/lb of Cu refining charges, US$5.0/oz of Au refining charges, US$33/wet metric tonnes (“wmt”) and US$20/wmt for shipping Cu and Fe concentrates respectively; waste mining cost of $1.75/t, mining cost of US$1.75/t ore, and process and G&A costs of US$7.53/t processed; average pit slope angles that range from 37.6º to 43.6º; a 2% royalty rate assumption. (2) Rounding as required by reporting guidelines may result in apparent summation differences between tonnes, grade and contained metal content. (3) Tonnage and grade measurements are in metric units. Contained gold ounces are reported as troy ounces.

Santo Domingo Project Estimated Mineral Resources as at October 31, 2018 

Inclusive of Mineral Reserves

Category Deposit Mt CuEq
Measured 66 0.81 0.61 0.081 30.9 254
Indicated  SDS/IN416 0.49 0.24 0.033 26.4 238
 Estrellita55 0.40 0.38 0.039 13.7 125
 Sub-Total417 0.48 0.26 0.034 25.0 225
Total Measured + Indicated 537 0.52 0.30 0.039 25.7 229
Inferred SDS/IN43 0.42 0.17 0.024 25.0 208
Estrellita5 0.32 0.31 0.030 12.3 108
Total Inferred 48 0.41 0.19 0.025 23.6 197

NOTES: Santo Domingo Project Mineral Resources shown on 100% basis (Capstone’s share is 70%). David Rennie, P. Eng., of Rosco Postle Associates Inc. and an independent Qualified Person responsible for the preparation of the Mineral Resources estimates for the Santo Domingo Sur, Iris Norte and Estellita deposits, which have an effective date of October 31, 2018. (1) Mineral Resources are classified according to CIM (2014) guidelines. (2) Mineral Resources are reported inclusive of Mineral Reserves. (3) Mineral Resources for SDS are reported at a cut-off grade of 0.125% CuEq, and for Estrellita at 0.125% CuEq. (4) Mineral Resources are constrained by Lerchs-Grossman pits. (5) Bulk density was estimated for each block and varies between 2.49 and 4.04 t/m3. (6) Cu equivalence was calculated using metallurgical recoveries, transport costs, smelter terms and royalties provided by Capstone. (7) Mineral Resources are estimated using metal prices of US$3.50/lb Cu, US$1,300/oz Au, and US$99/t FeO conc. (8) Numbers may not add due to rounding. (9) Only copper, gold and iron were recognized in the CuEq calculation; cobalt was excluded until further studies are completed to confirm reasonable prospects for eventual economic extraction.