Herderite and Sillimanite Physical Properties
Tenacity
Not Available
Tough
Solubility
Not Available
Not Available
Durability
Not Available
Not Available
Specific Gravity
2.90-3.02
3.20-3.26
Fracture
Subconchoidal, ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
Splintery
Cleavage
Indistinct on {110}
{010} perfect
Mohs Hardness
5-5.5
6-7.5
Chemical Composition
CaBePO 4(F,OH)Ulrich Henn and Claudio C.
Al 2SiO 5Michael OâDonoghue , Gems, Sixth Edition (2006)
Herderite and Sillimanite Chemical Formula
While comparing Herderite and Sillimanite 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 Herderite and Sillimanite chemical formula.
- Chemical formula of Herderite- CaBePO 4(F,OH)Ulrich Henn and Claudio C.
- Chemical formula of Sillimanite- Al 2SiO 5Michael OâDonoghue , Gems, Sixth Edition (2006)
Herderite and Sillimanite Specific Gravity
Another important criteria for qualitative analysis of gemstones is Herderite and Sillimanite Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Herderite and Sillimanite Optical Properties during the identification of gemstone. Specific gravity of Herderite is 3.20-3.26 whereas that of Sillimanite is 3.20-3.26.