Chemical element of metals. Cu comes from Cuprum, Fe comes from Ferrum, Ag from Argentum. The symbols were not followed by a period (full stop) as with abbreviations. Later chemical elements were also assigned unique chemical symbols, based on the name of the element, but not necessarily in English. For example, sodium has the chemical symbol 'Na' after the Latin "natrium". The same applies to "W" (wolfram) for tungsten, "Fe" (ferrum) for iron, "Hg" (hydrargyrum) for mercury, "Sn" (stannum) for tin, "K" (kalium) for potassium, "Au" (aurum) for gold, "Ag" (argentum) for silver, "Pb" (plumbum) for lead, "Cu" (cuprum) for copper, and
Zhejiang Huayou Cobalt buying cobalt mined by hand in DRC entirely. Zhejiang Huayou Cobalt Huayou Cobalt Co., Ltd is primarily a supplier of cobalt, including cobalt tetroxide, cobalt oxide, cobalt carbonate, cobalt hydroxide, cobalt oxalate, cobalt sulfate, and cobalt monoxide. It is headquartered in the Tongxiang Economic Development Zone of Zhejiang, China. A subsidiary, Congo DongFang International Mining, has been involved in several controversies around sourcing of cobalt in the Democratic Republic of the Congo. According to a joint Amnesty International and African Resources Watch report, Congo DongFang International Mining, a subsidiary of Huayou Cobalt, sources cobalt from primitive "artisanal" mines in the