Operations

Notes to above Mineral Reserves:

1. The Mineral Reserve estimates are current as of December 31, 2021 and are reported using the definitions in Item 1300 of Regulation S–K (17 CFR Part 229) (SK1300) and were prepared by the company’s technical staff.
2. Assumed metal prices for 2021 Mineral Reserves were $20.00 per ounce of silver, $1,400 per ounce of gold, $1.15 per pound of zinc, $0.95 per pound of lead.
3. Palmarejo Mineral Reserve estimates use the following key input parameters: Assumption of conventional longhole underground mining; reported above a variable gold equivalent cut-off grade that ranges from 1.94–2.51 g/t AuEq and an incremental development cut-off grade of 1.08 g/t AuEq; metallurgical recovery assumption of 93.1% for gold and 81.9% for silver; mining dilution assumes 1 meter of hanging wall waste dilution; mining loss of 5% was applied; variable mining costs that range from US$36.01–US$41.75/tonne, surface haulage costs of US$3.52/t, process costs of US$27.29/tonne, general and administrative costs of US$11.00/tonne, and surface/auxiliary support costs of US$3.19/tonne. Excludes the impact of the Franco-Nevada gold stream agreement at Palmarejo in calculation of Mineral Reserves.
4. Rochester Mineral Reserve estimates are tabulated within a confining pit shell and use the following input parameters: Rochester oxide recovery Au = 85% and Ag = 59%; Nevada Packard oxide recovery Au = 95% and Ag = 61%; with a net smelter return cutoff of $2.55/st oxide and US$2.65/st sulfide, where the NSR is calculated as resource net smelter return (NSR) = silver grade (oz/ton) * silver recovery (%) * silver price ($/oz) - refining cost ($/oz) + gold grade (oz/ton) * gold recovery (%) * gold price ($/oz) - refining cost ($/oz); variable pit slope angles that approximately average 43º over the lifeof-mine.
5. Kensington Mineral Reserve estimates use the following key input parameters: assumption of conventional underground mining; gold price of $1400/oz; reported above a gold cut-off grade of 0.143-0.201 oz/st Au; metallurgical recovery assumption of 95%; gold payability of 97.5%; mining dilution varies from 15-23%; mining loss of 5% was applied; variable mining costs that range from US$90.91–150.73/ton mined; process costs of US$46.93/ton processed; general and administrative costs of US$38.83/ton processed; and concentrate refining and shipping costs of US$60.00/oz sold.
6. Wharf Mineral Reserve estimate uses the following key input parameters: assumption of conventional open pit mining; reported above a gold cut-off grade of 0.010 oz/ton Au; metallurgical recovery assumption of 80%; royalty burden of US$56/oz Au; pit slope angles that vary from 34–50º; mining costs of US$2.15/ton mined, rehandle costs of US$1.65/ton rehandled, process costs of US$10.34/ton processed (includes general and administrative costs).
7. Silvertip Underground Mineral Resource estimates are reported using a net smelter return (“NSR”) cutoff of US$130- 160/tonne. Mineral Resources are reported insitu using the following assumptions: The estimate use the following key input parameters: lead recovery of 87-88%, zinc recovery of 81-82% and silver recovery of 88-89 %. Lead concentrate grade of 51-53%; zinc concentrate grade of 48-50%; mining dilution varies from 5-25%; mining loss of 5% was applied; mining costs of US$68.77/tonne; processing costs of US$58.20/tonne and US$46.49/tonne, where the NSR ($/tonne) = tonnes x grade x metal prices x metallurgical recoveries – royalties – TCRCs – transport costs over the life of the mine. 
8. Rounding of short tons, grades, and troy ounces, as required by reporting guidelines, may result in apparent differences between tons, grades, and contained metal contents.