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Cozamin Mine Estimated Mineral Reserves as at December 31, 2020

NOTE:  Tucker Jensen, P.Eng., Superintendent Mine Operations at Capstone Copper Corp., is the Qualified Person for this Cozamin Mineral Reserve update. Disclosure of the Cozamin Mineral Reserves as of December 31, 2020 was completed using fully diluted mineable stope shapes generated by the Maptek Vulcan Mine Stope Optimizer software and estimated using the 2020 MNFWZ and 2017 MNV resource block model by Garth Kirkham, P.Geo., FGC. Mineral Reserves are reported at or above a US$48.04/t net smelter return (“NSR”) cut-off in conventionally backfilled zones for 2020-2022, a US$51.12/t NSR cut-off in conventionally backfilled zones for 2023+, a US$56.51/t NSR cut-off in paste backfilled zones of Vein 10, and a US$56.12/t NSR cut-off in paste backfilled zones of Vein 20 using three formulae based on zone mineralization. Copper-silver dominant zones use the NSR formula: (Cu*50.476 + Ag*0.406)*(1-NSRRoyalty%). MNFWZ zinc-silver zones use the NSR formula: (Ag*0.259 + Zn*15.081 + Pb*15.418)*(1-NSRRoyalty%). MNV zinc-silver dominant zones use the NSR formula: (Ag*0.203 + Zn*13.163 + Pb*13.233)*(1-NSRRoyalty%). Metal price assumptions (in US$) of Cu = $2.75/lb, Ag = $17.00/oz, Pb = $0.90/lb, Zn = $1.00/lb and metal recoveries of 96% Cu, 84% Ag, 0% Pb and 0% Zn in copper-silver dominant zones, 0% Cu, 60% Ag, 92% Pb and 86% Zn in MNFWZ zinc-silver dominant zones, and 0% Cu, 53% Ag, 79% Pb and 75% Zn in MNV zinc-silver dominant zones. Mineral reserve calculations consider mining by long-hole stoping and mineral processing by flotation. Tonnage and grade estimates include dilution and mining losses. The NSR royalty rate applied varies between 1% and 3% depending on the mining concession, and royalties are treated as costs in mineral reserve estimation. An exchange rate of MX$20 per US$1 is assumed. All metals are reported as contained. Figures may not sum exactly due to rounding.

Cozamin Mine Estimated Mineral Resources as at December 31, 2020

NOTE: Mineral Resources are classified according to CIM (2014) definitions, estimated following CIM (2019) guidelines and have an effective date of December 31, 2020. Mineral Resources are reported inclusive of Mineral Reserves. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. The Independent Qualified Person for the estimates is Mr. Garth D. Kirkham, P.Geo., FGC., of Kirkham Geosystems Ltd. Mineral Resources are reported using four formulae for NSR based on mineralization. Copper-silver dominant zones use the NSR formula: (Cu*60.779 + Ag*0.485)*(1-NSRRoyalty%). Copper-zinc zones use the NSR formula: (Cu*58.430 + Ag*0.416 + Zn*15.368 + Pb*7.837)*(1-NSRRoyalty%). MNFWZ zinc-silver dominant zones use the NSR formula: (Ag*0.304 + Zn*18.323 + Pb*17.339)*(1-NSRRoyalty%). MNV zinc-silver dominant zones use the NSR formula: (Ag*0.256 + Zn*16.401 + Pb*14.977)*(1-NSRRoyalty%). Metal price assumptions (in US$) used to calculate the NSR for all deposits are: Cu = $3.25/lb, Ag = $20.00/oz, Zn = $1.20/lb and Pb = $1.00/lb. Recoveries used in the four NSR formulae are based on mineralization. Copper-silver dominant zones use the following recoveries: 96% Cu and 85% Ag. Copper-zinc zones use the following recoveries: 92% Cu, 79% Ag, 72% Zn and 42% Pb. MNFWZ zinc-silver dominant zones use the following recoveries: 60% Ag, 86% Zn and 92% Pb. MNV zinc-silver dominant zones use the following recoveries: 55% Ag, 77% Zn and 80% Pb. The NSR formulae include confidential current smelter contract terms, transportation costs and royalty agreements from 1 to 3%, as applicable. An exchange rate of MX$20 per US$1 is assumed. Totals may not sum exactly due to rounding. The NSR cut-off of US$50/tonne is based on operational mining and milling costs plus general and administrative costs. The Mineral Resource Estimate encompasses both the MNFWZ and the MNV. Drilling campaigns from 2018 have focused on the MNFWZ and no drilling has been performed on the MNV since 2017. The Mineral Resource considers underground mining by longhole stoping and mineral processing by flotation. No dilution is incorporated in the Mineral Resource. All metals are reported as contained. Mineral Resource estimates do not account for mining loss and dilution. These Mineral Resource estimates include Inferred Mineral Resources considered too speculative geologically to apply economic considerations for categorization as Mineral Reserves. However, it is reasonably expected that the majority of Inferred Mineral Resources could be upgraded to Indicated Resources.