Chemical Formula: CaF2

Chemical Name: Calcium Fluoride

Mineral Class: Halide

Mineral Notes: Fluorite is found in a wide range of geologic environments, ranging from inclusions in granite to replacement deposits in limestones. It is one of the most commonly collected minerals because of the beauty of its specimens, especially the well-formed cubic crystals.  

Description: This is an old-timer specimen which is at least 100 years old. It has an old Bottley label which dates the specimen back at least 70 years. Unfortunately because if its age it has been knocked about a bit and the largest crystal has a croner missing. However there a number of redeeming features. First, the colour is intense, which is rare for more recent specimens. Next, there are a few scattered Galena cubes, which provide a nice contrast to the Fluorite. And finally, there are a couple of really lovely clusters of gemmy twins, especially the formation between the two largest crystals. A great historic specimen.

Location: Blackdene Mine, Weardale, Co. Durham, England.