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 Mountains Duke George the Bearded, it has been held annually since. Also interesting is Ore Mountain cuisine, which is simple, but rich in tradition. Since 1998 the Ore Mountains have striven to achieve UNESCO World Heritage status as the Ore Mountain Mining Region ("Montanregion Erzgebirge"). Ore Mountains The Ore Mountains or Ore Mountain Range () ( ; ; both literally "ore mountains") in Central Europe have formed a natural border between Saxony and Bohemia for around 800 years, from the 12th to the 20th centuries. Today, the border between Germany and the Czech Republic runs just north of the main crest