Calamine brass Calamine brass Calamine brass is brass produced by a particular alloying technique using the zinc ore calamine directly, rather than first refining it to metallic zinc. Direct zinc smelting appears to have been unknown in Europe until the mid-18th century, even though the alloyed calamine brass was in use for centuries, and metallic zinc was produced directly via reducing-atmosphere smelting in India and China from the 12th century CE onwards. Brass is an alloy of copper and zinc and, when it was first developed, methods for producing metallic zinc were unknown. Metallurgists wishing to produce brass thus used calamine (actually
Group 11 element silver-plated copper wiring are found in some special applications. Copper occurs in its native form in Chile, China, Mexico, Russia and the USA. Various natural ores of copper are: copper pyrites (CuFeS), cuprite or ruby copper (CuO), copper glance (CuS), malachite, (Cu(OH)CuCO), and azurite (Cu(OH)2CuCO). Copper pyrite is the principal ore, and yields nearly 76% of the world production of copper. Silver is found in native form, as an alloy with gold (electrum), and in ores containing sulfur, arsenic, antimony or chlorine. Ores include argentite (AgS), chlorargyrite (AgCl) which includes horn silver, and pyrargyrite (AgSbS). Silver is extracted using the