Structure : Monoclinic
Hardness : 5
Specific Gravity : 3.53
Refractive index : 1.84 - 2.0
Doubly Refracting (bi-refraction) : 0.12
Sphene, also known as Titanite, is a brilliant yellowish-green, green or brown gemstone of high luster, unique color shades and, with brilliant cut, an intensive fire that can compete with diamond. While always in demand, sphene has been a rare gem on the market. New deposits have increased market quantities.
Sphene is named from the Greek word for wedge, because of its typical wedge shaped crystal habit. The mineralogical name "Titanite" derives from its titanium contents. Sphene is strongly pleochroic, displaying at least three colors (colorless, greenish-yellow, reddish) when looked at from different angles.
The brilliant cut serves the potential of "fire" in a sphene best. Depending on the clarity sphene is also shaped in cabochon and round cut. With a hardness rating of 5 -5.5 on the Mohs scale, sphene is a soft gemstone that needs care and qualifies best only for pendants, earrings or brooches. Sphene color can be changed to red or orange through heating.