Group 12 element people in the 17th century. German chemist Andreas Marggraf is usually given credit for discovering pure metallic zinc in a 1746 experiment by heating a mixture of calamine and charcoal in a closed vessel without copper to obtain a metal. Experiments on frogs by the Italian doctor Luigi Galvani in 1780 with brass paved the way for the discovery of electrical batteries, galvanization and cathodic protection. In 1880, Galvani's friend, Alessandro Volta, invented the Voltaic pile. The biological importance of zinc was not discovered until 1940 when carbonic anhydrase, an enzyme that scrubs carbon dioxide from blood, was shown to
Schlangenberg Nature Reserve the interest in the ore which was mostly used for weapons and vessels. The greatest interest in calamine had been in the 18th century when brass manufactures settled in Stolberg (Rhineland). For the production of the alloy they needed large amounts of calamine which was melted together with copper. Before 1800 digging small reaching only surface based ore was the only technique available to the miners. In the 19th century mining changed and more than 20 adits enabled the workers to reach calamine up to 105 m below the surface. During this time the Schlangenberg-area was perforated like a Swiss