Calamine brass slowly phased out as zinc smelting techniques were developed in Europe, which produced metallic zinc more suitable for brass production than calamine. However, the conversion away from calamine brass manufacture was slow; a British patent was awarded to William Champion in 1738, but the alloying of metallic zinc and copper to produce brass was not patented until 1781 (by James Emerson), and calamine brass mills persisted in South Wales until as late as 1858. The slow diffusion of this technology was probably the result of economic factors. Calamine brass Calamine brass is brass produced by a particular alloying technique using
Calamine (mineral) century demand for latten (brass) in England came from the needs of wool-carding, for which brass-wire combs were preferred, and battery pieces (brassware formed by hammering sheet brass in a battery mill.) The only known method for producing the alloy was by heating copper and calamine together in the cementation process and in 1568 a royal charter was granted to the Society of the Mineral and Battery Works to search for the mineral and produce brass, to reduce dependence on imported metal from Germany. Factories to exploit the process were established at Isleworth and Rotherhithe. By the late 17th century