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
Ore condition right order in "D" includes the condition that "D" must consist entirely of elements of the form "rs". Any domain satisfying one of the Ore conditions can be considered a subring of a division ring, however this does not automatically mean "R" is a left order in "D", since it is possible "D" has an element which is not of the form "s""r". Thus it is possible for "R" to be a right-not-left Ore domain. Intuitively, the condition that all elements of "D" be of the form "rs" says that "R" is a "big" "R"-submodule of "D". In fact the