Apatite is the most abundant phosphate on earth, and is the material that makes up our bones and teeth. It is also the main source of elemental phosphorus required by the plant kingdom, as well as for the production of toothpastes, fertilizers, fireworks, detergents and pesticides. Furthermore, despite its relatively low hardness (5.0), large apatite crystals are also occasionally fashioned into both faceted and cabochon-cut chatoyant gemstones, with the latter’s optical effect caused by the presence of fine, needle-like rutile inclusions within a stone.
Due to the fact that its crystals are found in almost every basic hue, apatite is able to mimic many other, often more valuable, gem varieties such as paraiba tourmaline. In fact, the name is derived from the Greek word meaning “deceit” for this very reason.
Formula: Ca5(PO)3(F,OH,Cl)3
Crystallography: Hexagonal, Crystal usually promatic or stubby