Fluorite
“The most colorful mineral”
Mineral
Fluorite is a calcium fluoride mineral that comes in nearly every color of the rainbow, sometimes displaying multiple colors in a single crystal. It gave its name to the phenomenon of fluorescence — glowing under ultraviolet light.
Composition
calcium fluoride (CaF₂)
Where Found
Derbyshire (England), Hunan Province (China), Illinois (USA), Asturias (Spain)
Mohs Hardness
4
Fun Fact
Fluorite literally gave us the word 'fluorescence' after scientists noticed it glowed a vivid blue-violet under UV light in 1852.
Test Your Knowledge
Why is fluorite used as a flux in steel manufacturing?
Related Specimens
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