1 Physical Properties
1.1 Tenacity
1.2 Solubility
Not Available
Not Available
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
2.50-3.002.90-2.98
1
7.18
1.5 Fracture
Uneven-Conchoidal, ConchoidalWalter Schumann, Gemstones of the world (2001)
Conchoidal, Brittle, Conchoidal, UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
1.6 Cleavage
3,6
Rare tabular and prismatic crystals. Usually occurs as fibrous, parallel veins that break off into cleavage fragments.
1.7 Mohs Hardness
1.8 Chemical Composition
The chief constituent Lapis Lazuli is Lazurite, with the following chemical formula: (Na,Ca)8Al6Si6O24(S,SO)4
CaSO 4Michael OâDonoghue , Gems, Sixth edition (2006) More from other references