Calcite var. Paper Calcite with Pyrite on Quartz with Chlorite inclusions

This large cabinet specimen of Calcite with Pyrite and Quartz is from 17 Level in Geevor mine at Pendeen, near St. Just, in Cornwall, England.  Geevor mine is sited on the cliff top close to Land’s End at the very southwest tip of Cornwall, overlooking the Atlantic Ocean.  This former tin and copper mine contained a rich variety of Calcite habits and this habit is termed “Paper Calcite” or “Schiefer Spar,” due to its paper-thin blades which commonly exceed 2 cm in width on this specimen.  The Calcite forms a jumbled, reticulated framework of such crystals with occasional infillings of millimetre-scale Pyrite crystals.  The Calcite covers a Quartz veinstone and masks a surface layer of chlorite-included Quartz crystals, some of which are visible around part of the periphery of the display face.  The specimen is accompanied with Sam Weller Minerals and County Maps & Minerals stock labels.