Apatite and Ettringite Physical Properties

Apatite and Ettringite Chemical Formula

While comparing Apatite and Ettringite physical properties, the important data you should know is its chemical composition. Since chemical formula defines the molecular structure of the crystal, most of the physical properties like color, tenacity, solubility are governed by Apatite and Ettringite chemical formula.

• Chemical formula of Apatite- Ca 5(PO 4) 3(F,OH,Cl)Walter Schumann , Gemstones of the world (2001) More from other references
• Chemical formula of Ettringite- Ca 6Al 2(SO 4) 3(OH) 12 26H 2OMichael O’Donoghue , Gems, Sixth Edition (2006)

Apatite and Ettringite Specific Gravity

Another important criteria for qualitative analysis of gemstones is Apatite and Ettringite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Apatite and Ettringite Optical Properties during the identification of gemstone. Specific gravity of Apatite is 1.77 whereas that of Ettringite is 1.77.