A gorgeous, 2.51″ wide, purple, cubic Fluorite crystal on bladed barite from the Cave-In-Rock district of Harden County, Illinois. Nicely terraced crystal faces caused by many smaller microscopic parallel crystal faces.
The Cave-In-Rock mining district of Hardin County, Illinois is world renown for it’s fluorite which is widely considered to be some of the highest quality fluorite in the world.
Fluorite is a halide mineral comprised of calcium and fluorine, CaF2. 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.