The former fluorspar mine has now mostly been infilled, the only part left exposed is for geological study. The restoration has been entered for an award by Lafarge (results due May 2011
Link. Mam Tor is in the background
SK1383 : Mam Tor.
Rake is another meaning for vein, although veins are long and sometimes rather thick. This rake runs along a fault line, horizontal slikensides have been observed, vertical displacement has been estimated at 20-30m. The lead vein here (PBS) has been mined for centuries, later on the gangue minerals (waste) became valuable and mined in their own right. Notably calcite, barytes and fluorspar, its also worth mentioning not far away the fluorspar 'blue john' is/was extracted.
They formed when around 2km down hot fluids around 120 degrees C dissolved ions from the shales /alongside
SK1383 : Mam Tor. These fluids moved laterally before reaching oxygenated and slightly sulphuric ground waters in the limestone, this caused the minerals to precipitate out. These waters moved along cracks and faults.
Also of major interest is the preserved cross section of a cave system, the phreatic tube and sink holes that normally are only seen by cavers are at the surface here. When formed they would have been under the water table, water (pressured?) formed a tube in the limestone. The sinkholes show erosional fluting. Some are infilled with windblown rock flour (from the glacial periods). The site is on private land and permission to enter must be sought.
This description was sourced from Stevie D and 'The geological setting of the lead mines in the northern part of the White Peak, Derbyshire' by Trevor D Ford (2010).