Staurolite and Ettringite Physical Properties
Tenacity
Brittle
Not Available
Solubility
Not Available
Partially soluble in water
Durability
Not Available
Not Available
Specific Gravity
3.7-3.8
1.77
Fracture
Subconchoidal, ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
Not Available
Cleavage
Distinct on {010}
Perfect on {10 1 0}
Mohs Hardness
7-7.5
2-2.5
Chemical Composition
(Fe,Mg,Zn) 2Al 9(Si,Al) 4O 22(OH) 2Ulrich Henn and Claudio C.
Ca 6Al 2(SO 4) 3(OH) 12 26H 2OMichael OâDonoghue , Gems, Sixth Edition (2006)
Staurolite and Ettringite Chemical Formula
While comparing Staurolite 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 Staurolite and Ettringite chemical formula.
- Chemical formula of Staurolite- (Fe,Mg,Zn) 2Al 9(Si,Al) 4O 22(OH) 2Ulrich Henn and Claudio C.
- Chemical formula of Ettringite- Ca 6Al 2(SO 4) 3(OH) 12 26H 2OMichael OâDonoghue , Gems, Sixth Edition (2006)
Staurolite and Ettringite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Staurolite and Ettringite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Staurolite and Ettringite Optical Properties during the identification of gemstone. Specific gravity of Staurolite is 1.77 whereas that of Ettringite is 1.77.