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Black Opal and Coral Physical Properties


Coral and Black Opal Physical Properties


Physical Properties

Tenacity
Not Available   
Not Available   

Solubility
Not Available   
Not Available   

Durability
Not Available   
Not Available   

Specific Gravity
1.97-2.22   
2.60-2.70   

Fracture
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)   
Irregular, Irregular, Gemstones of the world (2001)   

Cleavage
Not Available   
Not Available   

Mohs Hardness
6-6.5   
3-4   

Chemical Composition
SiO 2 + H 2OUlrich Henn and Claudio C.   
CaCO 3Ulrich Henn and Claudio C.   

Optical Properties >>
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Black Opal and Coral Chemical Formula

While comparing Black Opal and Coral 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 Black Opal and Coral chemical formula.

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Black Opal and Coral Specific Gravity

Another important criteria for qualitative analysis of gemstones is Black Opal and Coral Specific gravity. Specific gravity is the relative density of a gemstone compared with respect to density of water. Gemologists use Black Opal and Coral Optical Properties during the identification of gemstone. Specific gravity of Black Opal is 2.60-2.70 whereas that of Coral is 2.60-2.70.

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