Name: Fluorite
Brand: Crystal Classics
Price: 950 USD
Availability: InStock

Updated 5d ago

Fluorite

This small cabinet specimen from Blackdene mine at Ireshopeburn in Weardale is a wonderfully intriguing specimen. The first thing that one notices about this specimen - after its lovely purple colour - is its density, or lack of. This comes as quite a shock when picking it up. The reason for this is the porosity of the matrix which bears a striking resemblance to pumice which we all know is not possible. The clue to what has happened here lies beneath the gemmy purple, twinned Fluorite crystals on the display surface. Here, a velvety snow-white coating can be seen which might be Aragonite, but even this is not certain. What is clear, is that this white coating surrounds rhombic gaps in the matrix, indicating the dissolution of a carbonate. The most likely carbonates, given the dark residual colour, are Siderite or ferroan Dolomite and a couple of tiny fresh Dolomite crystals remain on the surface in one small area. The back of the specimen is partially encrusted with slightly weathered shallow rhombic Calcite crystals reaching 1.9 cm across. Being on the base, and being a relatively soft mineral, one of these larger Calcite crystals is slightly bruised along its edge. The largest Fluorite crystal reaches 1.1 cm on edge but most are in the 4 to 8 mm size range. Most are quite glassy, but the colour is generally paler purple except in the larger crystals where it deepens significantly. Minor chipping is evident to some of the crystals, but there is also the development of nice twinning growth lines on the surface of crystals. Ex George Farr, whose collection of Weardale Fluorites was not only comprehensive, but also extremely high quality. This Blackdene piece is certainly an unusual one, perfect for the Weardale connoisseur.

$950.00