Titanite is frequently called by the name Sphene, which was the more popular term for this mineral prior to 1982. In 1982, the IMA adopted the official name as Titanite and discredited Sphene. The name Sphene is still frequently used, especially in Europe. Sphene also persists as the more prevalent name for faceted Titanite gemstones or transparent crystal forms.
Titanite is known for its high luster and dispersion rate. This results in transparent Titanite crystals being brilliant, and opaque Titanite being highly reflective. It is also pleochroic, with different transparent crystals exhibiting different hues when viewed at different angles.
Titanite from a few localities contains thorium within its chemical structure. Such Titanite is slightly radioactive and will be metamict, resulting in those crystals having slightly rounded crystal edges and interior structural deficiencies.
Titanite is named for its titanium content. Its alternate name Sphene is named from the Greek term "sphenos", which means wedge, in allusion to the typical wedge-shaped crystals exhibited by this mineral.
For additional information, see the gemstone section on Sphene.
