1 Physical Properties
1.1 Tenacity
Not Available
Very brittle
1.2 Solubility
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
3.76-3.773.30-3.40
1
7.18
1.5 Fracture
UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009)
Conchoidal, Brittle, Conchoidal
1.6 Cleavage
{110} Perfect, {110} Perfect
{010} perfect, {110} distinct, {100} in traces
1.7 Mohs Hardness
1.8 Chemical Composition
(Fe,Mn) 7Si 7O 21Ulrich Henn and Claudio C.
AlO(OH)Walter Schumann , Gemstones of the world (2001) More from other references