sphene
[sfeen]
- a mineral, calcium titanium silicate, CaTiSiO5, occurring as an accessory mineral in a variety of crystalline rocks, usually in small wedge-shaped crystals.
Origin of sphene
First recorded in 1805–15, sphene is from the Greek word sphḗn wedge
Also called titanite.
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Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for sphene
Historical Examples
Reddish grains of sphene or of garnet are occasionally visible.
The rarer stones, sphene and epidote, likewise exhibit this property markedly.
A Text-Book of Precious Stones for Jewelers and the Gem-Loving PublicFrank Bertram Wade
The iron oxides, originally ilmenite, are usually altered to sphene.
Most gem-stones are harder than quartz, though precious opal, turquoise, moonstone and sphene are inferior to it in hardness.
Sphene, biotite and iron oxides are the other common constituents, but these rocks show much variety of composition and structure.
sphene
- a brown, yellow, green, or grey lustrous mineral consisting of calcium titanium silicate in monoclinic crystalline form. It occurs in metamorphic and acid igneous rocks and is used as a gemstone. Formula: CaTiSiO 5Also called: titanite
Word Origin
C19: from French sphène, from Greek sphēn a wedge, alluding to its crystals
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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sphene
[sfēn]
- A brown or yellow monoclinic mineral occurring as an accessory mineral in igneous and metamorphic rocks. It usually occurs as wedge or lozenge-shaped crystals. Chemical formula: CaTiSiO5.
The American Heritage® Science Dictionary
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