Heavy metals only mercury, lead and bismuth meet all of them. Despite this lack of agreement, the term (plural or singular) is widely used in science. A density of more than 5 g/cm is sometimes quoted as a commonly used criterion and is used in the body of this article. The earliest known metals—common metals such as iron, copper, and tin, and precious metals such as silver, gold, and platinum—are heavy metals. From 1809 onwards, light metals, such as magnesium, aluminium, and titanium, were discovered, as well as less well-known heavy metals including gallium, thallium, and hafnium. Some heavy metals are either
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