Slide 1: Corporate Update
Corporate Update May 2026 Pinto Valley, Arizona CAPSTONE COPPER CORP. | TSX:CS | ASX:CSC
Slide 2: Cautionary Notes
Cautionary Notes CAUTIONARY NOTE TO UNITED STATES INVESTORS REGARDING PRESENTATION OF MINERAL RESERVE AND MINERAL RESOURCE ESTIMATES As a British Columbia corporation and a “reporting issuer” under Canadian securities laws, we are required to provide disclosure regarding our mineral properties in ac
Slide 3: Cautionary Notes
Cautionary Notes CAUTIONARY NOTE REGARDING FORWARD LOOKING INFORMATION This document may contain “forward-looking information” within the meaning of Canadian securities legislation and “forward-looking statements” within the meaning of the United States Private Securities Litigation Reform Act of 19
Slide 4: Overview
Overview CAPSTONE COPPER CORP. | TSX:CS | ASX:CSC 4 CAPSTONE CAPSTONE COPPER COPPER CORP. CORP. | TSX:CS | TSX:CS | ASX:CSC | ASX:CSC 44
Slide 5: Copper in Top-Tier Jurisdictions in the Americas
29 Cu Copper COPPER IN TOP-TIER JURISDICTIONS IN THE AMERICAS Peer-Leading Declining Best-in-Class Strong Financial Copper Growth Cash Costs Mine Build and Position Operating Team +70% to ~375ktpa1 ~30% decrease1 +150 years of experience >$1B liquidity*,2 *Adjusted EBITDA and Available Liquidity are
Slide 6: District-Scale Growth in the Americas
District-Scale Growth in the Americas MANTOS BLANCOS (100%) Production by Region5 Producing Asset Development Stage Asset 2026E Production Open Pit 48-56 13+ year mine life kt Cu U.S. 20,000tpd mill capacity 23% +60ktpa cathode capacity3 Cu Ag Mexico PINTO VALLEY (100%) HQ, Vancouver, Canada 10% Chi
Slide 7: Clear Path to Transformational Growth
Clear Path to Transformational Growth Further organic Cu upside opportunities: • MB Phase II • SD Oxides • MV Phase II • Sierra Norte 500 $3.75 Annual Copper Production (kt) 400 ~375kt $3.00 C1 Cash Cost2 (US$/lb) ~265kt SANTO DOMINGO1 300 $2.25 225kt MV OPTIMIZED1 200 184kt $1.50 164kt MANTOVERDE1
Slide 8: Upcoming 2026 Catalysts
Upcoming 2026 Catalysts Q1 Q2 Q3 Q4 MV-O CONSTRUCTION AND RAMP-UP MV PHASE II & SANTO DOMINGO/SIERRA NORTE EXPLORATION PROGRAMS MANTOS BLANCOS PHASE II PERMIT APPLICATION & STUDY SANTO DOMINGO FID Executing peer-leading copper production growth, with a focus on safety, operational excellence and res
Slide 9: 2026 Production and Cost Guidance
2026 Production and Cost Guidance Delivering reliable results from a portfolio of long-life assets in top-tier jurisdictions FY 2026 Cu Production C1 Cash Costs1 (kt) (US$/lb Cu) Production and cost guidance notes: Sulphide Business • Mantoverde • Planned maintenance: Mantoverde2 64 – 74 $1.25 – $1.
Slide 10: Geopolitical Conflict – Recent Cost Pressures
Geopolitical Conflict – Recent Cost Pressures Supply: our mines continue to operate normally, 2026 Diesel Consumption1 with no direct impacts to our operations Expected consumption (April onwards): ~134M litres Costs: higher input prices putting upward pressure 2026 Sulphuric Acid Consumption3 on co
Slide 11: 2026 Capital Expenditures and Exploration Guidance
2026 Capital Expenditures and Exploration Guidance Investing in a strong foundation of operating assets and a peer-leading growth pipeline Sustaining Capital Expansionary Capital Capital Stripping Total (US$M) (US$M) (US$M) (US$M) Capital Expenditures Mantoverde2 $100 $150 $100 $350 Mantos Blancos $
Slide 12: Financial
Mantoverde Sulphide Plant Financial CAPSTONE COPPER CORP. | TSX:CS | ASX:CSC 12 CAPSTONE COPPER CORP. | TSX:CS | ASX:CSC
Slide 13: Balance Sheet Strength & Financial Flexibility
Balance Sheet Strength & Financial Flexibility With Disciplined Approach to Future Growth Net Debt / TTM EBITDA* Available Liquidity*,1 (US$M) Adjusted EBITDA* Sensitivity (US$M) 3.6x 2026E EBITDA 2 Annual EBITDA with MV-O Run-rate Production 2, 3 2, 3 Annual EBITDA with MV-O + Santo Domingo Run-rat
Slide 14: Strong Liquidity & Simplified Debt Structure
Strong Liquidity & Simplified Debt Structure Termed-Out Maturities Provide Financial Flexibility Capstone Balance Sheet Summary (as at March 31, 2026) As at Available US$M (1) Total Facility Size Interest Rate Tenor As at 31-Mar-26 31-Mar-26 Liquidity(4) Attributable At 31-Mar-25 Revolving Credit Fa
Slide 15: Operations
Pinto Valley Operations CAPSTONE COPPER CORP. | TSX:CS | ASX:CSC 15 CAPSTONE COPPER CORP. | TSX:CS | ASX:CSC
Slide 16: Mantoverde
2025/2026 Average Monthly Sulphide Plant Throughput (ktpd) Mantoverde Design throughput: 32 ktpd3 35 37 33 maintenance 34 Planned 33 33 32 32 30 30 Asset Overview 25 Unplanned motor 35-day maintenance strike Location Atacama Region, Chile; ~900m above sea level 20 action 18 18 Ownership Capstone (70
Slide 17: Mantos Blancos
Mantos Blancos Asset Overview 2024 - 2026 Throughput1 Performance (ktpd) Location Antofagasta Region, Chile; ~900m above sea level Confidence in Achieving Design Throughput Rates Ownership Capstone (100%) Planned maintenance Planned and and Chile power unplanned Planned Mine Type Open Pit (operating
Slide 18: Pinto Valley
Pinto Valley Pinto Valley District in Globe-Miami, Arizona Asset Overview Arizona (Globe-Miami), USA; Location ~1,000m above sea level Ownership Capstone (100%) Mine Type Open Pit (operating since 1975) Commodity Cu (primary), Mo/Au (secondary) Product(s) Sulphide concentrate + Grade A copper cathod
Slide 19: Cozamin
Cozamin C1 Cash Costs (US$/lb) 1,2 Asset Overview Location Zacatecas, Mexico; ~2,400m above sea level Strong by-product production and Ownership Capstone (100%) silver prices driving record quarterly Mine Type Underground (operating since 2007) $1.74 $1.78 C1 cash costs1,2 $1.32 Commodity Cu (primar
Slide 20: Growth & Exploration
Santo Domingo Growth & Exploration CAPSTONE COPPER CORP. | TSX:CS | ASX:CSC 20 CAPSTONE COPPER CORP. | TSX:CS | ASX:CSC
Slide 21: Expansion & Optionality Across the Portfolio
Expansion & Optionality Across the Portfolio MANTOVERDE – SANTO DOMINGO DISTRICT MV-SD 35km Apart PINTO VALLEY COZAMIN MANTOS BLANCOS MANTOVERDE SANTO DOMINGO Mine Life Extension and Fully Permitted Project; Mine Life Extension and Expansion Opportunities Across our Producing Assets Expansion Opport
Slide 22: Expansion & Optionality Across the Portfolio
Expansion & Optionality Across the Portfolio Project Status MV Optimized Construction underway, construction tie-in in Q3 2026 Near-Term +20kt copper/year incremental production1 Low capital intensity, brownfield expansion Santo Domingo Fully permitted, sanctioning +106kt copper/year incremental pro
Slide 23: Mantoverde Optimized
Mantoverde Optimized A Capital-Efficient Brownfield Expansion 2026 New tailings thickener 2024 2025 pumps Q1 Q2 Q3 Q4 Feasibility Study $176M Approval of Long-Lead Items Initial Capex for Brownfield DIA Permit Expansion Opportunity Detailed Engineering Sanctioning Construction & Tie-Ins (~15 days Q3
Slide 24: Santo Domingo Key Metrics at a Glance
Key Metrics at a Glance - July 2024 Feasibility Study Santo Domingo 29 Cu Copper 19 Year 106kt $0.28/lb Asset Overview Mine Life Avg. Annual C1 Cash Costs2 Cu Production2 (by-product basis) Location Atacama Region, Chile; low elevation at ~1,000m above sea level 1 Ownership Capstone (75%), Orion Res
Slide 25: Replicating Mine-Building Success in the Region
Replicating Mine-Building Success in the Region Project similarities and application of lessons learned to drive success Mantoverde Santo Domingo Mantoverde Development Project Project Produce sulphide ore with the Produce copper sulphide and iron addition of sulphide concentrator oxide concentrates
Slide 26: Santo Domingo Production and Costs
Santo Domingo Production and Costs Long Mine Life with a Robust Production Profile and First Quartile Costs LOM Production (kt) 200 Copper (kt) Iron Ore (kt) 180 CuEq. Production (kt) 160 Evaluating additional copper production optionality via Santo 140 Domingo oxides and integration of Sierra Norte
Slide 27: Santo Domingo Well-Positioned in Tier-1 District
Santo Domingo Well-Positioned in Tier-1 District Relative Advantage in Both Project Elevation and Access to Key Infrastructure Project Elevation and Distance to Key Infrastructure1,2 Santo Domingo has High Vicuña³ Elevation 5,000 a key strategic advantage from its low elevation and proximity to ke
Slide 28: Santo Domingo Path Forward
Santo Domingo Path Forward Advancing Remaining Workstreams in Parallel In Progress: Completed: In Progress: Engineering & (1) Study Balance Sheet Optimization Published updated Targeting <1.0x net debt to Progress detailed engineering; Feasibility Study for EBITDA (2) leverage and pursue infrastruct
Slide 29: Santo Domingo Illustrative Funding Structure
Santo Domingo Illustrative Funding Structure Prudent Approach to Capital Allocation in Pursuit of Transformational Growth $2.3Bn1 $1.2Bn2 Capstone Q1 2026 Balance Sheet Summary5 Remaining Funding Requirement Consolidated Net Debt6 of $738M Capstone portion of remaining funding 0.7x Net Debt / LT
Slide 30: Achieving District Scale Optimization in the MV-SD District
Achieving District Scale Optimization in the MV-SD District Unlocking a New World-Class Copper District with Additional Value Through Upside Opportunities Targeting +250,000 tonnes per year of low-cost copper production with a significant by-product of premium grade iron ore, with the potential to b
Slide 31: Mantos Blancos Upside Opportunities
Mantos Blancos Upside Opportunities Opportunity Highlights Stage / Impact • Controlled Potential Sulphidation (CPS) • Flotation activator for copper oxides in sulphide • At 20ktpd throughput, opportunity to Continuous circuit expand sulphide Cu production by Improvements • Energy Efficient Pulp Lift
Slide 32: Enhancing the Pipeline Through Exploration
Enhancing the Pipeline Through Exploration MANTOVERDE – SANTO DOMINGO DISTRICT MV-SD 35km Apart SANTO DOMINGO + PINTO VALLEY COZAMIN MANTOS BLANCOS MANTOVERDE SIERRA NORTE Mala Noche Vein SR Gap MNFWZ – Vein 20 MNV West MNFWZ Deep District Growth Study Mine Life Extension Near-Mine Exploration Near-
Slide 33: MV-SD: Exploration Program
MV-SD: Exploration Program Mantoverde Initial Two-Year $25M Exploration Mantoverde & Santo Domingo District1 Program Sierra Norte • Targeting higher copper grades 6 5 N • Exploring new areas adjacent or inside the current Mantoverde pits 4 • Testing high priority targets in the northern area of Nort
Slide 34: MV Initial Two-Year Exploration Program
MV Initial Two-Year Exploration Program Results from Phase 1 Overview of Phase 11: Highlights from Initial Results: 30,000-metres of drilling focused on areas • Higher than expected grades in Brecha Flores sector, where drill intercepts returned copper grades above those predicted adjacent to MV-O P
Slide 35: Santo Domingo and Sierra Norte Exploration Program
Santo Domingo and Sierra Norte Exploration Program Santo Domingo Exploration Potential IOCG type of mineralization with copper, gold, iron and cobalt ~340Mt of sulphide resource not included into reserves Key programs include: 54,700 metre drill program at Opportunity to define an oxide resource i
Slide 36: Responsibility
One of four new electric rope shovels at Mantoverde Responsibility CAPSTONE COPPER CORP. | TSX:CS | ASX:CSC 36 CAPSTONE COPPER CORP. | TSX:CS | ASX:CSC
Slide 37: Sustainable Development Strategy
Sustainable Development Strategy • Our Sustainable Development Strategy and GHG reduction targets follow a detailed review of our operations to establish a 2021 baseline. • The Strategy identifies five initial priorities with milestones, goals and targets supported by robust reporting and evaluation
Slide 38: GHG Emissions Reduction Targets
GHG Emissions Reduction Targets Climate Interim target: Reduce GHG emissions from fuel and power by 30% by 2030 compared to 2021 baseline year. Our carbon reduction strategy to 2030: • Transition to 50% renewable electricity in Chile by 2025 • Transition to >90% renewable electricity across Capstone
Slide 39: Investment Thesis
Mantos Blancos Open Pit Investment Thesis CAPSTONE COPPER CORP. | TSX:CS | ASX:CSC 39 CAPSTONE COPPER CORP. | TSX:CS | ASX:CSC
Slide 40: Three “Geo’s” Constraining Copper Supply Growth…
Three “Geo’s” Constraining Copper Supply Growth… LME copper prices gained +40% over 2025, the highest annual increase since 2009 • Declining Cu grades • More complex mining • Security of supply • Lack of new copper methods (deeper • Rising geopolitical discoveries underground mines, tensions • Lack
Slide 41: …While New Sources of Copper Demand Emerge
…While New Sources of Copper Demand Emerge Robust “traditional” demand amplified by emerging global trends • Population growth • Renewable power • AI & data centres • Urbanization • Electric vehicles • Onshoring of supply • Industrialization • Industry electrification chains • Increasing living • Gr
Slide 42: Capstone Copper – Capital Structure
Capstone Copper – Capital Structure Share Metrics Analyst Coverage Total Shares Outstanding1 764 million Barrenjoey J.P. Morgan Total Shares Outstanding (Fully Diluted)1 770 million Bradesco BBI Macquarie Shares Held as ASX CDIs2 174 million BMO Capital Markets Moelis & Company Market Cap3 US$6.5Bn
Slide 43: Copper in Top-Tier Jurisdictions in the Americas
29 Cu Copper COPPER IN TOP-TIER JURISDICTIONS IN THE AMERICAS Peer-Leading Declining Best-in-Class Strong Financial Copper Growth Cash Costs Mine Build and Position Operating Team ~70% to ~375ktpa1 ~30% decrease1 +150 years of experience >$1B liquidity*,2 *Adjusted EBITDA and Available Liquidity are
Slide 44: Appendix
Appendix CAPSTONE COPPER CORP. | TSX:CS | ASX:CSC 44 CAPSTONE COPPER CORP. | TSX:CS | ASX:CSC
Slide 45: Q1 2026 Actuals
Q1 2026 Actuals Q1 2026 Cu Production C1 Cash Costs1 Quarterly Adjusted EBITDA 1 (US$M) and (tonnes) (US$/lb Cu) Adjusted EBITDA Margin (%) Sulphide Business 350 60% Mantoverde2 13,733 $1.33 Mantos Blancos 10,501 $2.79 50% 300 Pinto Valley 10,711 $3.46 50% 45% Cozamin 5,930 $0.71 42% 250 40% Total S
Slide 46: 2022-2025: Executing Transformational Growth
2022-2025: Executing Transformational Growth 2022 2023 2024 2025 Annual Copper Production (kt) and Cu C1 Cash Cu C1 Cash Cu C1 Cash Cu C1 Cash C1 Cash Costs (US$/lb) 1 Production Costs1 Production Costs1 Production Costs1 Production Costs1 250 $3.00 (tonnes) (US$/lb Cu) (tonnes) (US$/lb Cu) (tonnes)
Slide 47: Proven Mine Building and Operating Leadership Team
Proven Mine Building and Operating Leadership Team +150 Years of Combined Mine Operations, Projects and Management Experience Cashel Meagher James Whittaker Raman Randhawa President & CEO SVP & COO SVP & CFO • +30 Years Experience • +25 Years Experience • +25 Years Experience • Former COO of Hudbay
Slide 48: Board of Directors
Board of Directors John MacKenzie Rick Coleman Non-Executive Chair Independent Director Peter Meredith Anne Giardini Lead Independent Director Independent Director Alison Baker Cashel Meagher Independent Director Director, President & CEO Gordon Bell Patricia Palacios Independent Director Independen
Slide 49: Mantos Blancos Exploration Potential
Mantos Blancos Exploration Potential Near-mine and District Opportunities Mantos Blancos Exploration Potential Opportunity to add additional sulphide and oxide resources Nora-Quinta below and lateral to the existing resource pit shell Veronica Nora-Quinta • Exploration Target: ~30-40Mt @ 0.5-0.7% Cu
Slide 50: Mantos Blancos Exploration Potential (Cont’d)
Mantos Blancos Exploration Potential (Cont’d) Near-mine and District Opportunities Mantos Blancos Block Geophysics exploration to identify appropriated volcanic rock (mineralized) package at depth and under the cover. Mantos Blancos Block mine mine prospective geology? 2.5 km ANT survey (seismic) ex
Slide 51: Pinto Valley: District Consolidation Potential
Pinto Valley: District Consolidation Potential • Globe-Miami is one of the oldest and most productive mining districts in the US • First recorded production occurred in 1878 since then, +15 billion lbs Cu have been produced • Since 1975, Pinto Valley has produced +4 billion lbs Cu, including ~0.5
Slide 52: MV-SD Pyrite Augmentation & Cobalt Opportunity
MV-SD Pyrite Augmentation & Cobalt Opportunity 27 Co Cobalt Heap Leach Ion-Exchange to Recover Cobalt Integration with Santo Domingo Proven Extraction Technology Planned Pyrite Concentrate Pipeline • Proven BPA ion-exchange technology • Commonly used in Ni/Co industry Santo Domingo • Selective for
Slide 53: Consolidated Estimated Mineral Resources
Consolidated Estimated Mineral Resources NOTES: Mineral Resources take into account mining activities to the effective date, where applicable and are reported insitu, using the 2014 CIM Definition Standards. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability.
Slide 54: Consolidated Estimated Mineral Reserves
Consolidated Estimated Mineral Reserves MINERAL RESERVES CONTAINED METAL TCu SCu ICu Zn Pb Mo Ag Au Fe Cu Zn Pb Mo Ag Au Fe3 Category kt % % % % % % g/t g/t % kt kt kt kt koz koz Mt Pinto Valley1 Proven 249,491 0.32 - - - - 0.007 - - - 803 - - 16 - - - 31-Dec-2025 Probable 50,724 0.30 - - - - 0.005
Slide 55: Sierra Norte
Sierra Norte Historical Mineral Resources Notes: Category Tonnes (Mt) CuT % CuS % Copper (kt) The Historical Mineral Resource was derived from the report “Actualización del Modelo Geológico y de la Estimación de Recursos Minerales del Proyecto Diego de Almagro” completed by Amec Foster Carmen-Paulin
Slide 56: General Enquiries
GENERAL ENQUIRIES Capstone Copper Corp. 2100 – 510 West Georgia Street Vancouver, BC - V6B 0M9 Capstonecopper.com info@capstonecopper.com +1-604-684-8894 Toll-free NA 1-866-684-8894 MEDIA & INVESTOR ENQUIRIES Daniel Sampieri, Vice President, Investor Relations +1-437-788-1767, Toronto, ON Michael Sl