Sunstone Metals (STM) AGM 2025 Presentation summary

Strategy and asset overview

• Focus on large, long-life, low-AISC gold-copper assets with scalable development and clear funding pathways.

• Portfolio includes two flagship projects: El Palmar in northern Ecuador and Bramaderos in southern Ecuador.

• El Palmar: 1.2Moz AuEq maiden JORC Resource from top 450m, with a 15M–45Moz AuEq exploration target across multiple zones.

• Bramaderos: 2.7Moz AuEq maiden JORC Resource, with a 4.2M–10.3Moz AuEq exploration target (Brama-Alba and Limon).

• Both projects are located in Ecuador, a region with low mining costs and strong government support for responsible mining.

Project details and resource estimates

• Bramaderos: 156Mt at 0.53g/t AuEq for 2.7Moz AuEq; exploration target of 3.3–8.6Moz AuEq in 255–360Mt at 0.40–0.74g/t AuEq.

• Limon (within Bramaderos): Exploration target of 0.9–1.7Moz AuEq in 30–44Mt at 0.9–1.2g/t AuEq; high-grade intersections up to 185m @ 2.85g/t AuEq.

• El Palmar: 64Mt at 0.60g/t AuEq for 1.2Moz AuEq; exploration target of 15–45Moz AuEq in 1.0–1.2Bt at 0.3–0.7g/t Au and 0.1–0.3% Cu.

• Drilling at El Palmar extends mineralisation beyond 1,750m deep, with significant potential for resource growth.

• Both projects have updated JORC-compliant resources and are advancing toward further studies and development.

Market and cost advantages

• Ecuador offers low energy and labour costs, placing projects in the lowest cost quartile globally.

• USD is the national currency, providing inflation protection.

• Record high gold prices and strategic demand for copper driven by the global energy transition and supply constraints.

• Major mining companies are active in Ecuador, and recent large-scale transactions highlight the region's attractiveness.