Cerium(III) fluoride (or cerium trifluoride), CeF3, is an ionic compound of the rare earth metal cerium and fluorine. It appears as a mineral in the form of fluocerite-(Ce) - a very rare mineral species related mainly to pegmatites and rarely to oxidation zones of some polymetallic ore deposits.  CeF3 may be used as a Faraday rotator material in the visible, near-infrared and mid-infrared spectral range.

Properties

Chemical formula : CeF3

Other names : Cerium trifluoride

Molar mass : 197.12 g/mol

Density : 6.16 g/cm3 (at 20 °C)

Melting point : 1460 °C (2,660 °F; 1,730 K)