Fluorite - penetration twinned (fluorescent)

Item Description

Penetration twins of Fluorite are perhaps the most attractive of the Fluorite twin habits for their dynamic, yet simple, form, and the Rogerley Mine is famous for producing these. Deep green and gemmy, this small miniature is classic for this locality. The larger crystal is 2 cm on longest side. Classic, intense bluish-purple fluorescence. In fact, it was English Fluorites that lent their name to the term 'fluorescence', that's how strongly they react to UV. Mining conditions can be difficult there, between water flow and hard country rock, so it is not surprising when a specimen comes out with some dings, like this piece has. Nonetheless, it is a good, representative specimen for both the habit and the locality. Formerly in the extensive collection of W & A Cook. #12701 !