Fluorite
Fluorite is a colorful mineral composed of calcium fluoride. It typically forms in cubic or octahedral crystals, but can also occur in massive or granular forms. Fluorite is known for its wide range of colors, including purple, green, blue, yellow, and colorless. It has a vitreous luster and can exhibit fluorescence under ultraviolet light. Fluorite is commonly used in jewelry, as decorative stones, and in the production of hydrofluoric acid and other industrial applications.