Solaris Resources (TSX: SLS; NYSE: SLSR) released results of a Pre-Feasibility Study (PFS) for its Warintza copper-molybdenum project in southeastern Ecuador, reporting a maiden open-pit mineral reserve of 1.3 billion tonnes at 0.41% copper-equivalent (CuEq) and a 22-year life-of-mine (LOM) constrained by tailings storage design. The study outlines average annual CuEq production of more than 300,000 tonnes in the first five years and over 240,000 tonnes during the first 15 years, with a post-tax NPV (8%) of US$4.617 billion, a post-tax IRR of 26%, and a 2.6-year post-tax payback.
Production, costs and economics
The PFS contemplates 60.2 Mt per year of throughput and LOM average Cu head grades of 0.31% with 84% Cu recovery. Average annual copper production is 230 kt in years 1–5 and 183 kt in years 1–15, alongside by-products averaging 8.6 kt/y molybdenum, 57 koz/y gold and 1.3 Moz/y silver during the first 15 years. LOM totals are 3,436 kt Cu, 154 kt Mo, 1.079 Moz Au and 26.6 Moz Ag. Unit operating costs total US$9.74/t milled in the first five years (US$8.75/t LOM), including mining US$3.38/t milled in the first five years (US$2.40/t LOM), processing US$5.58/t and G&A US$0.78–0.79/t. C1 cash costs are projected at US$0.59/lb Cu payable in the first five years (US$1.01/lb LOM) and AISC at US$0.85/lb in the first five years (US$1.25/lb LOM). Average annual EBITDA is US$1.9bn in the first five years and US$1.4bn during the first 15 years; average annual post-tax free cash flow is US$1.3bn and US$1.0bn over the same periods, respectively. Total post-tax free cash flow over the mine life is estimated at US$13.5bn. Initial capital (including 15.7% overall contingency) is US$3.729bn, with sustaining capital of US$1.713bn and closure costs of US$200m. Capital intensity over the first 15 years is ~US$15,440 per average tpa-CuEq. Base-case metal prices used for the economic analysis are copper US$4.50/lb, molybdenum US$20/lb, silver US$28/oz and gold US$2,800/oz for the first three years then US$2,500/oz thereafter. Sensitivity analysis indicates the post-tax NPV (8%) is most sensitive to copper price (or equivalently copper grade), followed by LOM operating costs, initial capital and molybdenum price.
Reserves, resources and strip ratio
Proven reserves total 797 Mt at 0.49% CuEq (0.37% Cu, 0.02% Mo, 0.05 g/t Au, 1.37 g/t Ag) and probable reserves 503 Mt at 0.28% CuEq (0.22% Cu, 0.01% Mo, 0.03 g/t Au, 1.19 g/t Ag). Payable metal assumptions are Cu 96.5%, Au 91%, Ag 91% and Mo 100%. Oxide and mixed material comprise <0.02% of total reserves. The LOM average strip ratio is 0.53:1; the first-five-years strip ratio is 0.37:1. A maiden 2025 Mineral Resource Estimate (MRE) reports Measured plus Indicated resources of 3.746 Bt at 0.32% CuEq (0.24% Cu, 0.01% Mo, 0.04 g/t Au, 1.19 g/t Ag) and Inferred resources of 2.092 Bt at 0.20% CuEq (0.16% Cu, 0.01% Mo, 0.02 g/t Au, 1.11 g/t Ag), at a 0.1% Cu cut-off within an optimized pit and an NSR cut-off of US$6.30/t. Oxide and mixed material account for <0.01% of resources. The company reports a 312% increase in Measured + Indicated tonnage relative to its 2024 MRE following an additional ~75,000 m of drilling (total ~177,118 m) and initial inclusion of Warintza West. The 2025 MRE incorporates silver grades and a change from a 0.25% CuEq reporting cut-off in 2024 to the stated NSR + 0.1% Cu cut-off. The effective date of the resource and reserve estimates is May 1, 2025.
CuEq methodology. For sulphide material: CuEq (%) = Cu (%) + 3.94 × Mo (%) + 0.52 × Au (g/t) + 0.01 × Ag (g/t). Mixed: CuEq (%) = Cu (%) + 3.76 × Mo (%) + 0.50 × Au (g/t) + 0.005 × Ag (g/t). Oxide: CuEq (%) = Cu (%). The PFS notes that mineral resources are inclusive of reserves and that resources that are not reserves do not have demonstrated economic viability.
Mine design and schedule
Warintza is planned as a conventional owner-operated open pit developed through two main pits (Warintza Central and Warintza East) and eight phases to sequence higher-grade ore early. The operation targets steady-state ore production of ~60.2 Mt/y after a two-year pre-strip. The primary fleet includes 120-t class cable shovels, 70-t wheel loaders and 320-t haul trucks, supported by dozers, graders and water trucks. Bench heights range 15–30 m; dual-lane haul roads are 40 m wide; slope angles are 36°–47° depending on geotechnical domains. Drilling and blasting will use 311 mm holes; annual explosives consumption peaks at ~46,000–58,000 t. Approximately 221 Mt of low-grade ore is scheduled for stockpiling and later processing, with LOM balances constrained by tailings storage limits; later years transition primarily to stockpile reclaim ahead of closure and reclamation.
Processing and product
The 165,000 t/d (60.2 Mt/y) concentrator is a conventional Cu-Mo flowsheet treating predominantly hypogene chalcopyrite with some supergene chalcocite/bornite. Ore will be primary- and secondary-crushed, then ground in two lines each with a 24 MW dual-pinion SAG mill and two 22 MW dual-pinion ball mills to P80 150 µm. Rougher flotation concentrate will be reground to P80 25 µm and cleaned in three stages to produce a bulk Cu-Mo concentrate for downstream separation. Copper and molybdenum concentrates will be dewatered for offsite smelting. Tailings will be thickened; cyclone stations will produce sand for dam construction with fines deposited in the Tailings Management Facility (TMF). The plant site is on steep terrain; footprint optimization and terracing may reduce earthworks costs. The company states both a high-quality copper concentrate and a clean molybdenum concentrate are expected, with non-material deleterious elements.
Infrastructure, logistics and power
The project is accessed by national/provincial highways with a final 58 km along the Limón–Warints road. Concentrate is planned to be transported to the Port of Bolívar near Machala; Bolívar (Machala) and Posorja (Guayaquil) are the planned ports for heavy equipment and materials. Power demand is estimated at 236 MW, to be supplied via a 62.1 km, 230 kV transmission line from the Bomboiza substation. Raw water will be supplied from a rainwater intake on the North Diversion Channel and transported by gravity; non-contact water will be diverted and contact water recycled from the TMF. Project communications will include a fibre-optic line with leased internet and radio backup, redundant switches, industrial Wi-Fi 6E (up to 40 Gbps), ~100 4K CCTV cameras with NVR redundancy, biometric/RFID access control, TETRA radios and a centralized monitoring centre. Site accommodation includes a main permanent camp near the plant and temporary camps at Piuntz, Yawi and Warintz for construction.
Tailings and waste rock
The TMF is designed to store ~1.3 Bt of tailings within the Warintza River basin over the projected mine life, contained by four dams in the Warints stream valley. Starter dams will be rockfill with a low-permeability core and a geomembrane liner on Dam No. 1, with centreline raises thereafter. Cycloning will separate coarse fractions for dam construction; fine fractions will be deposited in the TMF. Geochemical modelling indicates neutral pH at the final collection point based on current testing. The upstream Waste Rock Facility is designed for ~670 Mt and will be placed from downstream to upstream for stability.
Permitting, environmental and social
Solaris submitted an exploitation-phase Environmental Impact Assessment (EIA) in August 2024 to Ecuador’s Ministry of Environment, Water and Ecological Transition (MAATE), recently incorporated into the Ministry of Environment and Energy (MAE). The company reports it has addressed government inquiries and submitted the final Technical EIA, which is under review. In July 2025, the Sub-Secretary of MAE visited site and met Indigenous and local stakeholders regarding readiness for the Free, Prior and Informed Consultation (FPIC) process required under Ecuadorian law. The company states it is working with MAE to advance Exploitation Agreement permits, with progress on engineering facilities and water management. Environmental and social baseline programs cover biology, cultural resources, geochemistry, hydrology and groundwater.
Solaris reports formal community agreements with the Shuar centres of Warints and Yawi, including a Strategic Alliance (2019) and an Impacts & Benefits Agreement (IBA) signed in 2020 and later updated. As of September 2025, the company says it has signed cooperation agreements with all Indigenous organizations surrounding Warintza, including PSHA and FICSH, described as Ecuador’s two largest Shuar representative bodies, developed with government support. The agreements provide for employment, training, education, local procurement, infrastructure and direct financial benefits.
District context and property
Warintza is part of a porphyry corridor in southeastern Ecuador that includes the Mirador mine to the south and the San Carlos and Panantza deposits to the west. The property comprises nine metallic mineral concessions totalling 26,773 ha (268 km²). Solaris announced an option to acquire up to 100% of ten additional adjacent concessions (~40 km²) considered prospective for porphyry copper and epithermal gold. The site’s average elevation is ~1,200 m, with regional elevations from ~800–2,700 m and slopes of 25°–40°. The climate is tropical humid (Af), ~22.9°C average temperature and ~1,900 mm annual precipitation, permitting year-round operations.
Marketing, streaming and offtake
Production is planned to be sold as copper concentrate with gold and silver by-products and as molybdenum concentrate. The company has a gold streaming agreement with Royal Gold Inc. and a partial offtake agreement with Orion Resource Partners for copper and molybdenum concentrates; the remainder is to be sold on the open market. Treatment and refining charges are based on regional benchmarks for similar products.
Company statement
Matthew Rowlinson, CEO and President of Solaris Resources Inc., said: “Warintza checks every box: global scale, size, and longevity, technical simplicity in a supportive mining jurisdiction, exceptional economics driven by a world-class strip adjusted grade, and above all, optimal timing to production in a tightening copper market. With over 3.7 billion tonnes of Measured and Indicated Resources, 2.1 billion tonnes of Inferred Resources, 1.3 billion tonnes of Mineral Reserves, a low strip ratio, and early access to high-grade material, Warintza stands as one of the most compelling copper development assets anywhere in the world. We are fully funded for a construction decision through a US$200 million non-dilutive financing from Royal Gold earlier this year, while importantly retaining 100% ownership and full strategic control. In a copper market characterized by declining grades, few new discoveries, and increasingly complex permitting environments, Warintza is uniquely positioned to come online at the right moment, helping meet a critical global supply gap, while delivering strong returns to stakeholders. This is a rare window of opportunity: a generational discovery in a mining-friendly jurisdiction, with deep community support and a proven management team driving it forward. The future is bright, and we look forward to unlocking Warintza’s real value.”
Investor presentation
Solaris plans an online presentation today at 14:00 (Zug) / 08:00 (Toronto) via the Investor Meet Company (IMC) platform; the event is open to existing and potential shareholders, and questions can be submitted during the presentation. Registration details are provided in the company announcement.
Capital and operating breakdowns
Initial capital of US$3.729bn comprises (US$M): processing plant including earthworks (1,063), camp and site infrastructure (273), EPCM (256), mine equipment (304), TMF and water management (509), pre-stripping and haul road construction (179), other preliminary works/project team & G&A/IT/light vehicles (89), indirect costs (310), contingency (505) and VAT (242). Sustaining capital totals US$1.713bn, including open pit (736), infrastructure (356), TMF (239), water management (211), processing plant (65) and indirect/studies (106). LOM operating costs sum to US$3,116m mining (US$1.38/t moved), US$7,250m processing (US$5.58/t milled) and US$1,010m G&A (US$0.78/t milled).
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