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
Breinigerberg its calamine flora. The hill of "Schlangenberg" is 276 metres above sea level and originates in the former ore mine of Breinigerberg. Names like "Bleiweg", which means "Way of lead", even today, give hints to the history of the village. The calamine from the ore mine Breinigerberg was used exclusively in Stolberg for the production of brass. The history of Breinigerberg can be traced back to the Romans. Twenty five coins dated between 100 BC and the year 92/93 AD as well as remains of a Roman craftsmen settlement had been found in the village. The buildings show that the