1 Physical Properties
1.1 Tenacity
Not Available
Not Available
1.2 Solubility
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.5 Fracture
Brittle, UnevenArthur Thomas, Gemstones (2009), Brittle, Uneven
Uneven, Subconchoidal, UnevenArthur Thomas, Fibrous
1.6 Cleavage
Perfect
[110] perfect, [101] good, [010] distinct
1.7 Mohs Hardness
1.8 Chemical Composition
(Mg,Fe)Al 3(BO 4)(SiO 4)OUlrich Henn and Claudio C.
Al 3(PO 4) 2(OH,F) 3 · 5H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references