Pyromorphite (J-50)

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Beautiful lustrous crystals of pyromorphite measuring to 1.0 cm in size covering one side of matrix. There is a second-generation of crystallized pyromorphite present, these are more darker orange in color and botryoidal in nature. In outstanding condition, the quality is excellent. The Bunker Hill mine, located in Kellogg within Shoshone County, Idaho, is one of the most prolific and historically significant underground lead-zinc-silver operations in the Coeur d'Alene Mining District. Geologically, the deposit consists of extensive, high-grade hydrothermal replacement veins and fault-controlled orebodies hosted within the thick, heavily faulted Precambrian quartzites and argillites of the Belt Supergroup, particularly the Revett Formation. Hydrothermal fluids traveling along major structural lineaments deposited massive accumulations of argentiferous galena and sphalerite alongside a siderite and quartz matrix, with subsequent oxidation near the surface producing exceptional secondary minerals. Discovered in 1885 by Philip O'Rourke and Noah Kellogg, commercial mining began almost immediately and expanded rapidly under the Bunker Hill and Sullivan Mining and Concentrating Company, which developed a vast underground network extending over a mile deep and hundreds of miles horizontally. The mine and its associated smelting complex operated continuously as a major industrial engine until economic downturns, declining ore grades, and severe environmental compliance issues culminating in a major EPA Superfund designation forced the closure of primary operations in 1981. Following decades of water treatment and remediation, new corporate entities have undertaken extensive rehabilitation and exploratory drilling at the site, working toward a formal restart of underground commercial extraction through recent years.