mineral

Fluorite

Calcium Fluoride (CaF2)

Hardness: 4 (Mohs scale); Color: Purple, green, blue, yellow, or multi-colored; Luster: Vitreous (glassy); Crystal Structure: Isometric (cubic/octahedral); Cleavage: Perfect octahedral in four directions; Specific Gravity: 3.175–3.184.

Hardness: 4 (Mohs scale)
Color: Purple, green, blue, yellow, or multi-colored
Luster: Vitreous (glassy)

Identified April 5, 2026More mineral →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed through hydrothermal activity, typically in vein deposits where hot, mineral-rich fluids circulate through crustal rocks. It is found in a variety of geological environments ranging from sedimentary to igneous rocks.

Uses & applications

Used as a flux in steel making, in the production of hydrofluoric acid, and for high-performance camera lenses. Purple varieties are popular for jewelry, lapidary carvings, and mineral collection.

Geological facts

Fluorite is often called the most colorful mineral in the world. It is the defining mineral for hardness 4 on the Mohs scale. Many specimens exhibit fluorescence, glowing under ultraviolet light.

Field identification & locations

Identify by its softness (can be scratched by a pocket knife but not a penny), its octahedral cleavage, and its vibrant colors. Commonly found in China, Mexico, South Africa, and the USA (Illinois/Kentucky).