Color
White, Blue, Yellow, Brown, Green, Brownish, Greenish, gray
Blue, Greenish
Specific Gravity
2.65-2.90
3.31
Cleavage
{001} Perfect
{110} Good
Mohs Hardness
-9999
5.5-6
Chemical Composition
Al 2Si 4O 10(OH) 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
(Fe2+ ,Mg)Al 2(PO 4) 2(OH) 2Michael OâDonoghue , Gems, Sixth Edition (2006)
Pleochroism
-
Colorless blueAnthony et al
Transparency
Translucent
-
Refractive Index
1.534-1.601
1.639-1.680
Birefringence
0.050
0.041
Clarity
Translucent
TransparentUlrich Henn and Claudio C. Milisenda
Psychology
-
Communication
Healing
-
Emotional healing
Qualities Associated
Emotional Healing
Intuition & Communication