Highlights

The probable ore reserve increased by approximately 250%, from 125,000 tonnes to 438,000 tonnes of lithium carbonate equivalent.

The lithium carbonate development pathway generated a modelled net present value of US$1.09 billion and internal rate of return of 26.2%, alongside a projected US$4.2 billion in life-of-mine free cash flow.

The economic analysis uses an LCE reference price of US$27,300 per tonne, based on historical and forecast price inputs.

The next program includes updating resource and groundwater models using recent Mito and Demasia drilling, advancing definitive feasibility engineering, process optimisation, pumping tests and commercial engagement.

Lithium developer Pursuit Minerals Limited (ASX:PUR) has updated its development assessment for the wholly owned Rio Grande Sur project in Salta, Argentina. The new pre-feasibility study addendum examines higher production volumes and different saleable lithium products. Its central changes include a larger probable ore reserve, a staged growth profile and updated financial projections that remain dependent on development assumptions and market conditions.

Reserve Expansion Supports a Larger Plan

The probable ore reserve increased by approximately 250%, from 125,000 tonnes to 438,000 tonnes of lithium carbonate equivalent. The addendum evaluates staged production growth from 5,000 tonnes per annum to 17,500 tonnes per annum LCE. The updated reserve is derived entirely from Indicated Mineral Resources; Inferred Resources are not used in the forecast production schedules or financial modelling. This reserve base underpins the expanded scenarios described in the study.

Two Product Pathways Enter the Assessment

The lithium carbonate development pathway generated a modelled net present value of US$1.09 billion and internal rate of return of 26.2%, alongside a projected US$4.2 billion in life-of-mine free cash flow. An alternative lithium chloride pathway produced a modelled NPV of US$951 million and IRR of 27.1%. The figures are study estimates, not operating results, and apply to separate production routes with different processing and market assumptions.

Pricing and Capital Remain Material

The economic analysis uses an LCE reference price of US$27,300 per tonne, based on historical and forecast price inputs. The announcement also identifies a prevailing China Spot Price around US$13,707 per tonne on 6 November 2026. The difference underscores the importance of price sensitivity. The stage-two capital estimates include a 20% contingency; lithium chloride sales-price assumptions also require validation with potential customers.

Feasibility Work and Approvals Ahead

The next program includes updating resource and groundwater models using recent Mito and Demasia drilling, advancing definitive feasibility engineering, process optimisation, pumping tests and commercial engagement. Argentina’s RIGI Investment regime may offer benefits if eligibility and approvals are obtained. Financing, technical performance, regulatory conditions and lithium prices remain risks to achieving the study outcomes. The addendum supplements rather than replaces the February 2026 base-case pre-feasibility study.