Zinc for discovering pure metallic zinc, even though Swedish chemist Anton von Swab had distilled zinc from calamine four years previously. In his 1746 experiment, Marggraf heated a mixture of calamine and charcoal in a closed vessel without copper to obtain a metal. This procedure became commercially practical by 1752. William Champion's brother, John, patented a process in 1758 for calcining zinc sulfide into an oxide usable in the retort process. Prior to this, only calamine could be used to produce zinc. In 1798, Johann Christian Ruberg improved on the smelting process by building the first horizontal retort smelter. Jean-Jacques Daniel
Ore Metal Exchange aims to add uranium to its list of metals on warrant. The World Bank reports that China was the top importer of ores and metals in 2005 followed by the US and Japan. DILL, H.G. (2010) "The “chessboard” classification scheme of mineral deposits: Mineralogy and geology from aluminum to zirconium," Earth-Science Reviews, Volume 100, Issue 1-4, June 2010, Pages 1-420 Ore An ore is an occurrence of rock or sediment that contains sufficient minerals with economically important elements, typically metals, that can be economically extracted from the deposit. The ores are extracted from the earth through mining; they