Calcite

A magnificent large cabinet specimen of Cornish Calcite from the mines close to, and a little north east of the town of Liskeard in northern Cornwall.  Surprisingly, for all of its mineral diversity, Cornwall is relatively deficient in Calcite, so specimen from this district are highly prized.  Probably the most famous mine is Wheal Wrey at St. Ive where the Calcite is superb and without doubt a Cornish classic.  Wonderful specimens can be seen in the Royal Cornwall Museum in Truro.  This specimen has similar crystal morphology to that at Wheal Wrey, but this does not imply it is from here; the comparison is made only to illustrate the characteristic traits of Calcite in this area.  Overgrowing a solid matrix of mixed Calcite, Pyrite and minor Chalcopyrite, large, truncated trigonal Calcite crystals create a stunning display piece with prisms ranging from a few millimetres to 4.5 cm across.  The crystals are translucent off-white, have smooth and glassy prism faces and a flat rippled pinacoidal termination.  The crystals are hexagonal in cross-section, with alternate wide and narrow prism faces.  On close inspection the rippled terminations are formed from multiple adjacent rows of skewed rhombohedral crystals, fascinating when viewed through a low power loupe.  Under LWUV the entire specimen fluoresces pale salmon reddish-pink.  A gorgeous specimen of Cornish Calcite.