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