Description

#1321 – A mineral specimen featuring a dark green Fluorite cluster cubes up to .8 inches on edge.  On the other end of the specimen a gemmy dark green penetration cubes up to .67 inches on edge rests on matrix.  This specimen comes from the Lady Annabella Mine, Eastgate, Weardale, County Durham, England.  The Fluorite cubes fluoresce blue under UV light.  The dimension of this specimen is 4 x 2 x 1.1 inches.  The fluorite at the Lady Annabella Mine originated from hydrothermal fluids circulating through fractures in the Great Limestone during the Devonian era, likely influenced by a nearby granite intrusion. These hot, mineral-rich brines moved upward through the existing fault systems, including the splay shear that hosts the mine, causing minerals like fluorite to precipitate and crystallize in the resulting cavities and breccias as temperature and pressure conditions changed.