1 Physical Properties
1.1 Tenacity
Not Available
Very brittle
1.2 Solubility
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.5 Fracture
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001)
Conchoidal, Brittle, Conchoidal
1.6 Cleavage
Not Available
{010} perfect, {110} distinct, {100} in traces
1.7 Mohs Hardness
1.8 Chemical Composition
Ca 2 MgAl 2 BSi 4 O 15 OH Gemdat.org, Management Team (2012)
AlO(OH)Walter Schumann , Gemstones of the world (2001) More from other references