Apatite (calcium phosphate) is a clear to opaque stone that comes in many colors, including green, yellow, blue, violet, and yellow-green (called asparagus stone). Some apatite stones show a cat's eye asterism. This stone is rarely used in jewelry because it is brittle and soft. Apatite comes from the Greek word for "deceit," because it was easily confused with other minerals. Brazil is the traditonal source of gem quality apatite. Recent finds of what is now widely referred to as "NEON" APATITE in Madagasgar have added to the popularity of this gem. The neon is a Green Blue stone with good saturation--leading to the moniker.