Mineral Species: Fluorite
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.
Description: This is a very rare and unusual combination of blue-green and pale-lavender Fluorite in one specimen. The crystals of both forms are extremely well-formed, transparent and therefore very gemmy. There is extensive twinning, especially of the larger blue-green crystals. There is no visble damage.
Location: St. Peter's Mine, Allendale, Northumbria, England.