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
Hunan Nonferrous Metals took control of the holding company "Hunan Nonferrous Metals Holding Group Co., Ltd." in 2011. On 1 August 2006 it purchased a 9.73 percent share in Compass Resources NL of Australia for 30 million Australian dollars. Hunan Nonferrous Metals Hunan Nonferrous Metals Holding Group Co., Ltd. is a nonferrous metals company of China. It is a subsidiary of China Minmetals, which in turn indirectly under supervision of State-owned Assets Supervision and Administration Commission. Some of the assets of the conglomerate was listed in Hong Kong Stock Exchange from 2006 to 2015 as "Hunan Nonferrous Metals Corporation Limited" (SEHK: 2626). (The