Ettringite and Almandine Physical Properties
Tenacity
Not Available
Not Available
Solubility
Partially soluble in water
Not Available
Durability
Not Available
Not Available
Specific Gravity
1.77
3.95-4.30
Fracture
Not Available
Conchoidal, Brittle, Conchoidal, Brittle, Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Brittle, Conchoidal
Cleavage
Perfect on {10 1 0}
none
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 3Al 2(SiO 4) 3Arthur Thomas , Gemstones (2009)
Ettringite and Almandine Chemical Formula
While comparing Ettringite and Almandine 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 Almandine chemical formula.
- Chemical formula of Ettringite- Ca 6Al 2(SO 4) 3(OH) 12 26H 2OMichael OâDonoghue , Gems, Sixth Edition (2006)
- Chemical formula of Almandine- Fe 3Al 2(SiO 4) 3Arthur Thomas , Gemstones (2009)
Ettringite and Almandine Specific Gravity
Another important criteria for qualitative analysis of gemstones is Ettringite and Almandine Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Ettringite and Almandine Optical Properties during the identification of gemstone. Specific gravity of Ettringite is 3.95-4.30 whereas that of Almandine is 3.95-4.30.