Phosphate minerals and their features
Phosphate mineral, any of a group of naturally occurring inorganic salts of phosphoric acid, H3(PO4). More than 200 species of phosphate minerals are recognized, and structurally they all have isolated (PO4) tetrahedral units.
Turquoise
Chemical Formula : CuAl6(PO4)4(OH)8·4H2O
Mohs Scale : 5 - 6
Crystal System : Triclinic
The word turquoise dates to the 17th century and is derived from the French turquois meaning "Turkish" because the mineral was first brought to Europe through the Ottoman Empire
Pyromorphite
Chemical Formula : Pb5(PO4)3Cl
Mohs Scale : 3,5- 4
Crystal System : Hexagonal
Specific gravity : 6.5 - 7.1
From China
Wavellite
Chemical Formula : Al3(PO4)2(OH,F)3·5H2O
Mohs Scale : 3,5- 4
Crystal System : Orthorhombic
Specific gravity : 2.36
Vivianite
Chemical Formula : Fe2+3(PO4)2·8H2O
Mohs Scale : 1,5-2
Crystal System : Monoclinic
Apatite
Chemical Formula : Ca5(PO4)3(F,Cl,OH)
Mohs Scale : 5
Crystal System : Hexagonal
Specific gravity : 3.16