Titanite

Formula: CaTi(SiO4)O. Often contains minor Al, Fe3+ and F.

Colour: Brown, green, yellow, orange, rose-red, black, beige, grey, colourless, grey-blue, bluish

Lustre: Adamantine, Resinous

Hardness: 5 – 5½

Specific Gravity: 3.48 – 3.6

Crystal System: Monoclinic

Member of: Titanite Group. The titanium analogue of Malayaite and Vanadomalayaite.

Name: First recognized in 1787 by Marc August Pictet, but only described and named in 1795 by Martin Klaproth for its titanium content. A common synonym, sphene (from the Greek sphenos (σφηνώ), meaning wedge, for its common wedge-shaped crystals), was introduced in 1801 by Rene Just Haüy.

Co-Type Localities: Titanite occurrence, Hauzenberg, Passau District, Lower Bavaria, Bavaria, Germany; Town of Philipstown, Putnam Co., New York, USA; Rossie, St. Lawrence Co., New York – USA

Dimorph of: Triclinic Titanite

Isostructural with: Durangite, Tilasite,

Also known as sphene, this calcium titanium silicate forms flattened wedge-shaped crystals, commonly twinned with prominent re-entry angles; massive, compact and lamellar forms are also found. It occurs as an accessory mineral in igneous rocks; in schists, gneisses and other metamorphic rocks, and is also found as a detrital mineral in some sedimentary deposits. An As- and Na-rich mineral related to titanite was just approved under the name arsenatrotitanite.