Fluorite
Species
Common · CaF₂
Calcium fluoride that crystallises in sharp cubes and octahedra. Occurs in a wide spectrum of colours due to trace element impurities and radiation exposure. The physicist George Stokes coined the word fluorescence from fluor-spar in 1852.
Identity
- Formula
- CaF₂
- Chemical class
- Halide
- Also known as
- Fluorspar, Blue John (banded variety)
Crystallography
- Crystal system
- Cubic
- Habits
- Cubic, Octahedral, Massive
- Fracture
- Subconchoidal
Physical properties
- Mohs hardness
- 4
- Density
- 3.18 g/cm³
- Luster
- Vitreous
- Colors
- purple, blue, green, yellow, colorless, pink, brown, black
- Streak
- white
- Transparency
- Transparent, Translucent
Geology
- Origins
- Hydrothermal, Igneous, Sedimentary
- Host rocks
- Granite, Limestone and chalk
- Associated minerals
- Quartz, Calcite, Barite, Galena
- Geography
- China, Mexico, Spain, UK, Germany, USA
Classification
- Rarity
- Common
- Gem quality
- Yes
Arcane properties
- Affinity
- Arcane, Mind
- Effects
- Mind, Warding
- Planar origin
- Material Plane
Sources
- M. Pasero and others, IMA Commission on New Minerals, Nomenclature and Classification, The New IMA List of Minerals, updated September 2026. International Mineralogical Association (CNMNC), 2026.
- Fluorite. Mindat.org (Hudson Institute of Mineralogy).
- J. W. Anthony, R. A. Bideaux, K. W. Bladh, M. C. Nichols, Fluorite. Mineral Data Publishing, Handbook of Mineralogy, 2001.
- G. G. Stokes, On the Change of Refrangibility of Light. Philosophical Transactions of the Royal Society of London, 142, 463-562, 1852.
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