This is a fluorite octahedron from the Shangrao, China. Fluorite naturally grows in octahedral forms, but most of the loose octahedral crystals have been cleaved by the miners along the cleavage plane of the crystal.
is a halide mineral comprised of calcium and fluorine, CaF2. The word fluorite is from the Latin fluo-, which means to flow. In 1852 fluorite gave its name to the phenomenon known as fluorescence, or the property of fluorite to glow a different color depending upon the bandwidth of the ultraviolet light it is exposed to. Fluorite occurs commonly in cubic, octahedral and dodecahedral crystals
in many different colors. These colors range from colorless and completely transparent to yellow, green, blue, purple, pink or black. Purples and greens tend to be the most common colors seen.