Sunstone Reports 2.7Moz AuEq Bramaderos Resource, Eyes Scoping Study

Corporate Progress and Strategic Options

Sunstone Metals Limited has reported significant progress in multiple corporate discussions during the September 2025 quarter. Several parties have conducted due diligence and site visits, with talks advancing to a stage where a formal offer may soon be finalised. These discussions encompass a range of strategic options, including corporate transactions and strategic investments, reflecting Sunstone’s efforts to unlock value from its substantial gold and copper discoveries in Ecuador.

Bramaderos Project – Resource Update and Exploration Upside

At the Bramaderos Gold and Copper Project in southern Ecuador, Sunstone is preparing an updated Mineral Resource estimate (MRE) aimed at increasing the Indicated Resource classification. This update will underpin a planned scoping study for the Brama-Alba deposit, which currently holds a JORC-compliant resource of 2.7 million ounces gold equivalent (AuEq). Recent extensive surface rock channel sampling at Brama-Alba and adjacent targets like Melonal and Copete has highlighted ongoing potential for resource growth and expansion of the mineralised footprint.

The Bramaderos project also features a porphyry Exploration Target estimated between 3.3Moz and 8.6Moz AuEq within 255 to 360 million tonnes at grades ranging from 0.40 to 0.74g/t AuEq. Additionally, the nearby Limon gold-silver epithermal deposit presents an Exploration Target of 0.9Moz to 1.7Moz AuEq, offering a potential lower capital cost, open-pit development opportunity to complement the larger porphyry systems.

El Palmar Project – Maiden Resource and Large Exploration Target

In northern Ecuador, Sunstone’s El Palmar project has delivered a maiden Mineral Resource estimate of 1.2 million ounces AuEq based on the outcropping T1 gold-copper porphyry target. This deposit is one of five identified targets within the concession and holds promise as a large open-pit opportunity. The company has also defined a high-conviction Exploration Target ranging from 15 million to 45 million ounces AuEq across 1.0 to 1.2 billion tonnes at grades between 0.3g/t to 0.7g/t gold and 0.1% to 0.3% copper, indicating significant upside potential pending further drilling and evaluation.

Financial Position and Funding Outlook

Sunstone ended the quarter with a cash balance of $2.2 million, bolstered by $1.6 million raised through the exercise of options issued in 2024. An additional 259 million in-the-money options remain outstanding, representing potential further funding of approximately $1.9 million. Exploration expenditure for the quarter was $1.6 million, focused primarily on surface sampling and mapping activities to support resource updates. The company continues to explore strategic partnerships and funding avenues to sustain its exploration and development programs.

Looking Ahead

Sunstone’s ongoing corporate discussions, combined with promising exploration results and resource upgrades, position the company at a pivotal juncture. The upcoming scoping study at Bramaderos and further drilling at El Palmar and other targets will be critical in defining the scale and economics of these projects. Meanwhile, the potential formal offer emerging from corporate talks could provide the capital and strategic support needed to accelerate development.