Kupferschiefer
The Kupferschiefer (German for Copper Shale, also called Copper Slate) or Kupfermergel (Copper Marl), (T1 or Z1) is an extensive and remarkable sedimentary unit in Central Europe. The relatively monotonous succession is typically 30 to 60 centimetres (12 to 24 in) and maximum 2 metres ( ft) thick, but extends over an area of 600,000 square kilometres (230,000 sq mi) .