East Java's Gua Macan Holds 276 Million Tonnes of Copper-Gold Resources

PT Merdeka Copper Gold Tbk (MDKA) has announced an updated Mineral Resource Estimate (MRE) for the Gua Macan Porphyry Copper-Gold Project, a deposit discovered through the company’s exploration activities in the Tujuh Bukit mineral district, East Java, Indonesia. Gua Macan is located within the Mining Business Licence (IUP) area of PT Bumi Suksesindo (BSI), one of Merdeka’s strategic mining assets in East Java. The project is fully owned by the Merdeka Group through its subsidiary entities. This updated Mineral Resource Estimate further strengthens Gua Macan’s position as part of Merdeka’s long-term copper and gold growth portfolio, while providing additional support for evaluating the potential for open-pit mine development. The latest Mineral Resource Estimate totals 276 million tonnes (Mt) at an average grade of 0.23 grams of gold per tonne (g/t Au) and 0.16 per cent copper (Cu), containing approximately 2.0 million ounces of gold (Moz Au) and 430,000 tonnes of copper (kt Cu). This figure represents an increase of 70 Mt (+25 per cent), 0.40 Moz of gold, and 103 kt of copper compared to the previous Mineral Resource Estimate announced in December 2025. Indicated Mineral Resources nearly doubled to 217 million tonnes from the previous 112 million tonnes, reflecting the successful conversion of resources through an additional 26 diamond drill holes and refinements to the geological model. Albert Saputro, President Director of PT Merdeka Copper Gold Tbk, stated that the updated Mineral Resource Estimate for Gua Macan is another important milestone for Merdeka and reflects the value of the company’s exploration strategy. He noted that starting as an internally generated exploration target in 2023, Gua Macan has rapidly grown into a significant, gold-rich porphyry copper-gold resource located near the currently operating Tujuh Bukit Gold Mine. The Main Porphyry zone is now the primary value contributor within the Gua Macan deposit. This zone holds a resource of approximately 110 million tonnes grading 0.36 g/t Au and 0.23 per cent Cu, containing around 1.3 million ounces of gold and 257,000 tonnes of copper. Although it accounts for only about 40 per cent of the total Mineral Resource tonnage, the Main Porphyry contributes roughly 65 per cent of the gold content and 60 per cent of the copper content in the Gua Macan deposit. Mineralisation at Gua Macan has been defined over an area of approximately 1 kilometre by 1 kilometre and extends from the surface to a drilling depth of around 600 metres. The mineralisation system remains open at depth, indicating potential for further resource additions as exploration and technical studies continue.