1 Physical Properties
1.1 Tenacity
1.2 Solubility
Dilute acid
Not Available
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.5 Fracture
Subconchoidal, ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
ConchoidalGemdat.org, Uneven
1.6 Cleavage
Distinct on {010}, imperfect {110} and {011}
{111} Indistinct, {111} Indistinct, {111} Indistinct
1.7 Mohs Hardness
1.8 Chemical Composition
CaCO 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Fe2+ Al 2O 4Gemdat.org , Management Team (2012)