South32 has extended the expected life of its Sierra Gorda copper mine in Chile after a significant increase in the operation’s ore reserves.The company said on Tuesday that its ore reserve estimate for Sierra Gorda had increased 61% to 1.1-billion tonnes, extending the mine’s initial reserve life by about five years to 2045. The update follows 85,000m of additional drilling across 200 holes completed between 2023 and 2025.South32 approved an expansion of the mine’s processing capacity in July. The expansion is expected to increase copper production by about 30% from 2031 and lift the amount of ore processed each day from 135,000 tonnes to 165,000 tonnes.The miner said the updated reserves are expected to support 19 years of mining at the higher processing rate.South32’s estimate of the copper, gold and molybdenum-bearing material at Sierra Gorda also increased 8% to 1.87-billion tonnes.South32 expects Sierra Gorda to produce 3.548-million tonnes of copper between 2026 and 2045, along with 982,000 ounces of gold and 93,000 tonnes of molybdenum.South32 said there is also potential to expand the reserve through further exploration. The orebody remains open at depth, while drilling in the Catabela Northeast area, an exploration area near the Sierra Gorda mine, has found copper deposits. However, the company said extending mining beyond the current approvals will require regulatory work. The existing environmental approvals cover the mining areas until 2035, while South32 plans to start the process of extending the approval by 2030.South32 owns 45% of Sierra Gorda and jointly controls the mine with Polish mining company KGHM Polska Miedź, which owns the remaining 55%.Sierra Gorda is an open-pit copper mine in the Antofagasta region of northern Chile. It produced its first ore in 2015 and currently processes 135,000 tonnes of ore a day. This is expected to increase to 165,000 tonnes a day by 2031 after the planned expansion.South32 acquired its 45% stake in Sierra Gorda in February 2022 from Japanese companies Sumitomo Metal Mining and Sumitomo Corporation for about $1.4bn upfront.At the time, South32 described the acquisition as a way to increase its exposure to copper, which it viewed as a metal with strong long-term demand.Business Day