Calcium fluoride

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Calcium fluoride
IUPAC name
Calcium fluoride
Other names
Calcium difluoride
Molar mass 78.07 g/mol
Appearance White crystalline solid (single crystals are transparent, natural crystals tend to be colored due to impurities)
Odor Odorless
Density 3.18 g/cm3
Melting point 1,418 °C (2,584 °F; 1,691 K)
Boiling point 2,533 °C (4,591 °F; 2,806 K)
0.0015 g/100 ml (18 °C)
0.0016 g/100 ml (20 °C)
Solubility Reacts with sulfuric acid
Insoluble in organic solvents
Vapor pressure ~ 0 mmHg
Safety data sheet Sigma-Aldrich
Flash point Non-flammable
Related compounds
Related compounds
Sodium fluoride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Calcium fluoride is an inorganic salt of calcium, with the chemical formula CaF2. It occurs in nature as the mineral known as fluorite or fluorspar. It is a relative inert and insoluble compound.



Calcium fluoride will react with a strong acid, such sulfuric acid to yield calcium sulfate and hydrogen fluoride.

CaF2 + H2SO4 → 2 HF + CaSO4


Calcium fluoride is a white solid compound. Single crystals are transparent. It is extremely poorly soluble in water (0.0016 g/100 mL at 20 °C) and insoluble in organic solvents. It has a melting point of 1,418 °C and boils at 2,533 °C.


Calcium fluoride occurs naturally as the mineral fluorite, that can be purchased from mineral sellers. Certain homeopathy tablets also contain calcium fluoride. Purer calcium fluoride is available from chemical suppliers.

Calcium fluoride optic objects, such as lens, windows, filters, prisms are an interesting application of the substance. At least one website offers many such items.


Calcium fluoride can be prepared by reacting a fluoride, such as sodium fluoride with a soluble calcium salt, such as calcium chloride.

2 NaF + CaCl2 → CaF2 + 2 NaCl

Calcium fluoride precipitates out of the solution, which is filtered and dried.




Calcium fluoride has poor solubility in water. Contact with strong acids, such as sulfuric acid should be avoided, as it will generate toxic hydrofluoric acid. This includes gastric (hydrochloric) acid: do NOT swallow calcium fluoride!


Calcium fluoride should be stored away from strong acids.


Calcium fluoride does not require any special disposal and can be dumped in the trash.


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