Green Beryl

From The Gemology Project
Revision as of 22:39, 31 October 2006 by Africanuck (talk | contribs)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search
Green Beryl
Chemical composition Be3Al2(SiO3)6 Beryllium aluminium silicate
Crystal system Hexagonal
Habit Prismatic
Cleavage Imperfect, basal
Hardness 7.5
Optic nature Uniaxial -
Refractive index 1.564 - 1.593
Birefringence 0.005-0.006
Dispersion Low, 0.014
Specific gravity 2.68-2.72
Lustre Vitreous
Pleochroism Weak to distinct