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, Uneven
Conchoidal, Brittle, Conchoidal
1.6 Cleavage
None
{010} perfect, {110} distinct, {100} in traces
1.7 Mohs Hardness
1.8 Chemical Composition
Mn 3B 7O 13ClMichael OâDonoghue , Gems, Sixth Edition (2006)
AlO(OH)Walter Schumann , Gemstones of the world (2001) More from other references