1.28Moz reserve and A$40 million placement define Tesoro’s next phase

Ternera reserve establishes a 13-year mine plan

Tesoro Gold Limited (ASX:TSO) has put a mineable number around its Ternera discovery in Chile, declaring a maiden Ore Reserve of 42.8 million tonnes at 0.93 grams per tonne gold for 1.28 million ounces. The reserve sits entirely within a single open pit and supports more than 13 years of production at the planned 3.0 million tonnes per annum processing rate.

The conversion is substantial: 87% of the 1.47Moz classified as Measured and Indicated in the August resource estimate is now included in the reserve. That provides Tesoro with a more defined technical base for its Definitive Feasibility Study, although the reserve remains supported by PFS-level mine designs, schedules and modifying factors rather than an operating mine or final investment decision.

Higher-confidence resource follows 27,162 metres of drilling

The reserve followed completion of an 80-hole, 27,162-metre infill programme. Tesoro’s updated Ternera Mineral Resource Estimate stands at 51.6Mt at 1.10g/t gold for 1.82Moz, constrained within a US$3,500 per ounce optimised open-pit shell and reported at a 0.30g/t cut-off.

Measured and Indicated resources account for approximately 1.47Moz, including a 95koz Measured component defined for the first time. The drilling produced several wide intercepts, including 101 metres at 1.12g/t gold and 96.4 metres at 0.86g/t, while the company also reported higher-grade intervals such as 10 metres at 6.14g/t. These results underpin the resource update, but individual drill intersections should not be read as a project-wide grade forecast.

The shift from definition drilling to growth drilling gives the exploration story a second act. Tesoro said drilling has moved towards extensions around Ternera, including Ternera East and northern targets, as well as broader discovery work at El Zorro. Earlier drilling had delivered the Ternera infill programme, which the company said supported the resource upgrade and forthcoming reserve.

A$40 million placement resets the funding runway

The financial disclosure is the less glamorous but immediately practical part of the quarter. Tesoro ended 30 September with A$9.28 million in cash and reported A$5.64 million of exploration and evaluation expenditure during the quarter. On the Appendix 5B calculation, that left an estimated 1.61 quarters of funding, with no unused finance facilities.

Tesoro subsequently received firm commitments for an approximately A$40 million placement at A$0.73 per share. About A$32.8 million is covered by existing placement capacity, while the remaining A$7.2 million requires shareholder approval. The company said the proceeds will fund the Ternera DFS, permitting, resource expansion drilling, wider exploration and working capital. The A$40 million placement therefore addresses a clearly disclosed near-term funding constraint, but it also brings new shares into issue and leaves part of the raise conditional.

DFS, permitting and ownership decisions move to centre stage

During the quarter, Tesoro advanced mine planning, process engineering for the proposed 3.0Mtpa plant, dry-stack tailings design, power and water planning, environmental reporting and financing work. Baseline environmental fieldwork was completed, with the Environmental Impact Assessment and sectorial permit documents still progressing. The DFS remains targeted for completion during calendar 2026.

Tesoro also signed a binding term sheet to acquire the remaining 5% interest in its Chilean subsidiary, which would lift its direct interest in El Zorro from 90.63% to 95.4%. The consideration is approximately 11.7 million new Tesoro shares, with completion subject to shareholder approval and other conditions. That proposal, alongside the deferred placement tranche, puts the expected December shareholder meeting on the critical path for both funding and project ownership.