Fluorite, also known as fluor-spar, is a mineral composed of Calcium Fluoride. It is a widely occurring mineral and is often found with metallic minerals such as Galena and Sphalerite, but also with Barite, Quartz and Calcite. It may fluoresce strongly in ultraviolet light. Although green is the most common color, it can also be red, purple, blue, yellow and white.