Habit: prismatic, colloform, massive, granular, earthy.
Color: white, yellow, green, red,
or blue (the color is often due to the presence of rare earths).
Diaphaneity: transparent
to translucent.
Luster: subresinous.
Streak: white. Cleavage: (0001) indistinct, (1010)
indistinct.
Fracture: conchoidal.
Chemical: soluble in HCl, and HNO3.
Occurrence: found
in all type of rocks (igneous, sedimentary, and metamorphic).
Source of phosphorus and phosphoric acid, manufacture of fertilizers, laser crystals.
A natural calcium phosphate (usually containing fluorine) occurring in the earth’s crust as phosphate rock. It is also the chief component of the bony structure of teeth.
A naturally occurring
phosphate of calcium, CaF2.Ca3(PO4)3.
Apatite is a highly complex hexagonal structured mineral
form of calcium phosphate [Ca5(PO4)3.(OH,F,Cl)]2. It
is the most common of all phosphate minerals.
Depending upon the dominance of fluorine, chlorine or
hydroxide, apatite is called fluorapatite, chlorapatite or
hydroxyapatite, respectively.
Apatite often occurs widely as an accessory
mineral with igneous rocks, such as pegmatite. It also
occurs in regional and contact metamorphic rock,
especially limestone. Large deposits of apatite are found
in Russia.
Apatite, a major source of phosphorus, is used in the
production of fertilizers. Enamel of the teeth is composed
chiefly of apatite.
