Ongoing Exploration Programs At Kensington & Las Chispas

CHICAGO, IL – Coeur Mining, Inc. reported on the exploration programs at its Las Chispas underground silver and gold mine in Sonora, Mexico and its Kensington underground gold mine in Alaska.
Recent intercepts reflect some of the highest grades drilled – Drilling at the North Las Chispas vein, discovered in September 2024 and located immediately east of underground infrastructure, has returned exceptionally high-grade mineralization. Intercepts include 1.0 feet at 4.61 ounces per ton (“oz/t”) gold and 392 oz/t silver (or 0.3 meters at 158 grams per metric ton (“g/t”) gold and 13,430 g/t silver). Growth at recent Augusta discovery – The Augusta vein continues to expand along strike, with standout intercepts including 1.2 feet at 0.81 oz/t gold and 113.8 oz/t silver (or 0.4 meters at 27.7 g/t gold and 3,903 g/t silver). Accelerated drilling strategy – Based on year-to-date success, near-mine expansion and infill programs have been ramped up to nine drill rigs to target additional resource growth.
New high-grade zones identified – Drilling at the Upper and Lower Kensington zones continues to encounter multiple parallel veins returning high grades over mineable widths, including 7.1 feet at 11.5 oz/t (2.2 meters at 395.9 g/t gold) in Upper Kensington Zone 30B. Elmira expansion and new discovery – Drilling has confirmed up-dip expansions and continuity across several vein zones at the Elmira deposit, a key source of current mine production, located approximately 2,500 feet (760 meters) from the Kensington deposit. Results include 9.1 feet at 1.5 oz/t (2.8 meters at 52.1 g/t gold). A new discovery, the Elmira Hanging Wall Mineralization (EHM), also identified 2.1 feet at 2.3 oz/t (0.6 meters at 80 g/t gold) providing another area for future expansion potential.
“Our sustained focus on organic growth through brownfield exploration over the past several years continues to set us apart by generating multiple new discoveries and driving consistent reserve and resource increases, leading to meaningful mine life extensions and higher returns on invested capital across the portfolio,” said Mitchell J. Krebs, Chairman, President and Chief Executive Officer.
“Since acquiring Las Chispas in February 2025, an upscaled scout and expansion drill program has delivered early success by expanding resources in several key veins within the Gap Zone and the Las Chispas Block with the potential for future reserve conversion. Particularly encouraging are the extremely high-grade intercepts returned in the Las Chispas Block, including one assay of 1.4 feet at 390 ounces per ton on a silver equivalent basis—grades that have not typically been encountered outside the Babicanora Block.
“At Kensington, the recently concluded multi-year exploration and development program, which helped drive an increase in its reserve-based mine life to five years, is serving as a springboard for replacing depletion and is identifying potential sources of higher grade material while providing Kensington with significantly enhanced operational flexibility.”