Heavy metals are here treated as light metals and, in general, are not further considered. The heaviness of naturally occurring metals such as gold, copper, and iron may have been noticed in prehistory and, in light of their malleability, led to the first attempts to craft metal ornaments, tools, and weapons. All metals discovered from then until 1809 had relatively high densities; their heaviness was regarded as a singularly distinguishing criterion. From 1809 onwards, light metals such as sodium, potassium, and strontium were isolated. Their low densities challenged conventional wisdom and it was proposed to refer to them as "metalloids" (meaning "resembling
Institute of Cast Metals Engineers Institute of Cast Metals Engineers The Institute of Cast Metals Engineers (ICME), originally the British Foundrymen's Association is a British professional engineering institution founded in 1904. It publishes the Foundry Trade Journal, which was established in 1902. It was founded as the British Foundrymen's Association in 1904. It was given a Royal Charter on 25 November 1921. On 11 October 2000, it changed its name to the Institute of Cast Metals Engineers. It is licensed by the Engineering Council to assess candidates for inclusion on its Register of professional Engineers and Technicians. The Institute's address is ICME Metalforming Centre, 47