Operations

Mineral Reserves Notes:

1. Effective Date of December 31, 2024, accounting for drilling activities and mining depletion at the Caraíba Operations since the September 30, 2022 effective date of the Mineral Resource and Mineral Reserve estimates contained in the Caraíba Operations Technical Report.
2. Mineral reserves included within stated mineral resources. All figures have been rounded to reflect the relative accuracy of the estimates. Summed amounts may not add due to rounding.
3. Mineral Reserve estimates were prepared in accordance with the Canadian Institute of Mining, Metallurgy and Petroleum (“CIM”) Definition Standards for Mineral Resources and Mineral Reserves, adopted by the CIM Council on May 10, 2014 and the CIM Estimation for Mineral Resources and Mineral Reserves Best Practice Guidelines, adopted by CIM Council on November 29, 2019, using geostatistical and/or classical methods, plus economic and mining parameters appropriate for the deposit. 
4. Mineral reserves are based on a long-term copper price of US$3.60 per pound (“lb”), and a USD:BRL foreign exchange rate of 5.10. Mineral Reserves are the economic portion of the Measured and Indicated Mineral Resources. Mining dilution and recovery factors vary for specific Mineral Reserve sources and are influenced by factors such as deposit type, deposit shape, stope orientation, and selected mining methods. In the mine design of the Pilar and Vermelhos underground mines, certain stopes include Measured and Indicated as well as Inferred Resource blocks. In these instances, Inferred Resource blocks within the defined mining shape were assigned zero grade. In 2024, Inferred blocks assigned zero grade totaled approximately 6 tonnes for the Deepening Extension Zone, 2,412 tonnes for the Pilar Underground Mine, and approximately 13,700 tonnes for the Vermelhos Underground Mine. Development occurring within marginal ore, above the operational cut-off grade, has also been included in the Mineral Reserve estimate. Dilution occurring from Measured and Indicated Resource blocks was assigned a grade based on the Mineral Resource grade of the blocks included in the dilution envelope. 
5. In the mine design of the Pilar and Vermelhos underground mines, certain stopes include Measured and Indicated as well as Inferred Mineral Resource blocks. In these instances, Inferred Mineral Resource blocks within the defined mining shape were assigned zero grade. Development occurring within marginal ore, above the operational cut-off grade, has also been included in the Mineral Reserve estimate. 
6. The September 30, 2022 Mineral reserves were classified according to the CIM Standards and the CIM Guidelines by Mr. Beck Nader, FAIG (#4472), of BNA Mining Solutions, and Alejandro Sepúlveda, Registered Member (#0293) (Chilean Mining Commission) of NCL Ingeniería y Construcción SpA. Both of whom are independent Qualified Persons as such term is defined under NI 43-101. Please refer to the Company’s “2023 Annual Information Form” dated March 7, 2024 for additional technical information. The updated Mineral Resource and Mineral Reserve estimates as at December 31, 2024 was prepared under the supervision of and approved by Cid Gonçalves Monteiro Filho, SME RM (04317974), MAIG (No. 8444), FAusIMM (No. 329148), Resource Manager of the Company, who is a “qualified person” within the meanings of NI 43-101.

Mineral Resources Notes:

1. Effective Date of December 31, 2024, accounting for drilling activities and mining depletion at the Caraíba Operations since the September 30, 2022 effective date of the Mineral Resource and Mineral Reserve estimates contained in the Caraíba Operations Technical Report.
2. Presented mineral resources inclusive of mineral reserves. All figures have been rounded to the relative accuracy of the estimates. Summed amounts may not add due to rounding.
3. Mineral Resources have been constrained within developed 3D grade-shells and lithology models applying a 0.45% and 0.20% copper grade envelope for high and marginal grade, respectively. Within these envelopes, Mineral Resources for underground deposits were constrained to those volumes ensuring Reasonable Prospects for Eventual Economic Extraction after application of 0.51% copper cut-off grade as well as a marginal cut-off grade of 0.33% copper, used for Pilar Mine underground Mineral Resources and 0.52% copper and of 0.34% copper for Vermelhos Mine underground Mineral Resources. 
4. For open pit projects 0.13% copper cut-off grade were used for Mineral Resources reporting. Mineral Resources were estimated using ordinary kriging within 5m by 5m by 5m block sizes. Mineral Resources are shown inclusive of Mineral Reserves. The low-grade envelope, using a cut-off grade of 0.20% copper for underground deposits, was used to develop a dilution envelope and development block model to better define the grade of blocks within the dilution envelope in the planning and design of underground stopes and planned development within the mineral reserve estimates and LOM production plan.
5. The September 30, 2022 Mineral resources were classified according to the CIM Standards and the CIM Guidelines by Mr. Porfirio Cabaleiro Rodriguez, FAIG, (#3708), with contributions from others at GE21. All are independent Qualified Persons as such term is defined under NI 43-101. Please refer to the Company’s “2023 Annual Information Form” dated March 7, 2024 for additional technical information. The updated Mineral Resource and Mineral Reserve estimates as at December 31, 2024 was prepared under the supervision of and approved by Cid Gonçalves Monteiro Filho, SME RM (04317974), MAIG (No. 8444), FAusIMM (No. 329148), Resource Manager of the Company, who is a “qualified person” within the meanings of NI 43-101.

Mineral resources which are not mineral reserves do not have demonstrated economic viability.