Phosphate Family
Phosphates are rocks which are primarily composed of phosphorous. Phosphorous can be from an inorganic or organic source with much being from seawater.
Well known phosphate gems include:
Apatite - usually hydroxyapatite, fluorapatite and chlorapatite (written as Ca10(PO4)6(OH)2, Ca10(PO4)6F2 and Ca10(PO4)6Cl2) - Occurs in many colors with a hardness of 5
Lazulite - Magnesium Iron Aluminium Phosphate - Dark blue with a hardness of 5.5 to 6
Turquoise - Copper Aluminum Phosphate - Blue to green with moderate hardness of a 5-6
Variscite - Hydrous Aluminum Phosphate - Green to Green/Yellow often softer than turquoise
