Fluorite
Halide · CaF₂ · also: Fluorspar
Fluorite is calcium fluoride, famous for glassy cubic crystals in every colour, perfect octahedral cleavage and often glowing under UV light.
What is fluorite?
Fluorite is calcium fluoride, one of the most colourful minerals in the collecting world. It grows as glassy cubes and octahedra in purple, green, blue, yellow and colourless, often colour-zoned within a single crystal. It cleaves neatly into octahedra and frequently fluoresces (the word “fluorescence” is named after it).
Properties
- Chemical formula
- CaF₂
- Category
- Halide
- Hardness (Mohs)
- 4
- Crystal system
- Cubic (isometric)
- Lustre
- Vitreous
- Streak
- White
- Colour
- Purple, green, blue, yellow, colourless
- Cleavage / fracture
- Perfect octahedral (four directions)
How to identify fluorite
- →Glassy cubes (or octahedra) in vivid colours, often zoned.
- →Perfect octahedral cleavage: corners break off cleanly.
- →Hardness exactly 4 on the Mohs scale (its reference mineral).
- →Many specimens glow blue or purple under UV light.
Where fluorite is found
Superb fluorite comes from England (Rogerley, Weardale), China, Illinois (USA), Spain and Switzerland.
Fluorite finds on minShelf
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