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Rutile on pyrophyllite from Mono County, Calif.—B.M. Shaub
Commercially important titanium mineral (titanium dioxide, TiO). It forms red to reddish brown, hard, brilliant metallic, slender crystals. Rutile has minor uses in porcelain and glass manufacture as a colouring agent and in making some steels and copper alloys. It is also used as a gem, but synthetic rutile is actually superior to natural crystals for gem use; it has fire (flashes of colour) and brilliance (light deflection) like those of diamond. Rutile is mined in Norway and is widespread in the Alps, the southern U.S., Mexico, and elsewhere.
This entry comes from Encyclopædia Britannica Concise. For the full entry on rutile, visit Britannica.com.