1 Physical Properties
1.1 Tenacity
Very brittle
Not Available
1.2 Solubility
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
3.30-3.402.69-2.72
1
7.18
1.5 Fracture
Conchoidal, Brittle, Conchoidal
Uneven, Conchoidal, Gems, Sixth Edition (2006)
1.6 Cleavage
{010} perfect, {110} distinct, {100} in traces
Perfect on {001}, less perfect on {010}, intersecting at near 90°; distinct on {110}
1.7 Mohs Hardness
1.8 Chemical Composition
AlO(OH)Walter Schumann , Gemstones of the world (2001) More from other references
(Na,Ca)1-2Si3-2O8