Calamine (mineral) Calamine (mineral) Calamine is a historic name for an ore of zinc. The name "calamine" was derived from "lapis calaminaris", a Latin corruption of Greek "cadmia (καδμία)", the old name for zinc ores in general. The name of the Belgian town of Kelmis, "La Calamine" in French, which was home to a zinc mine, comes from that. In the 18th and 19th centuries large ore mines could be found near the German village of Breinigerberg. During the early 19th century it was discovered that what had been thought to be one ore was actually two distinct minerals: Although chemically and
Tantalum pentoxide tantalite are called coltan. Tantalite was discovered by Anders Gustaf Ekeberg at Ytterby, Sweden, and Kimoto, Finland. The minerals microlite and pyrochlore contain approximately 70% and 10% Ta, respectively. Tantalum ores often contain significant amounts of niobium, which is itself a valuable metal. As such, both metals are extracted so that they may be sold. The overall process is one of hydrometallurgy and begins with a leaching step; in which the ore is treated with hydrofluoric acid and sulfuric acid to produce water-soluble hydrogen fluorides, such as the heptafluorotantalate. This allows the metals to be separated from the various non-metallic