Kyanite

Kyanite is a typically blue silicate mineral, commonly found in aluminum-rich metamorphic pegmatites and/or sedimentary rocks.  Kyanite is also known as disthene, rhaeticite and cyanite. Kyanite has been used as a semiprecious gemstone,, which may display cat's eye. Color varieties include recently discovered orange kyanite from Tanzania. The orange color is due to inclusion of small amounts of  manganese in the structure. Kyanite's elongated, columnar crystals are usually a good first indication of the mineral, as well as its color (when the specimen is blue).