Physical Properties |
|
Chemical formula | Be3Al2Si6O18 |
Class | Cyclosilicate Rings of linked tetrahedra |
Crystal system | Hexagonal |
Habit | Hexagonal prisms |
Color | Colorless Blue Red Green (emerald) Pale greenish blue (aquamarine) Rose (morganite) Gold (heliodor) |
Hardness | 7.5 to 8 |
Specific gravity | 2.7 to 2.9 |
Cleavage | Poor (001) |
Fracture | Even |
Luster | Vitreous to resinous |
Transparency | Transparent to translucent |
Streak | White |
Optical Properties |
|
PPL | Colorless Non-pleochroic |
XPL | 1st order gray |
δ | 0.006 |
after Perkins, 315-316 |
Beryl in Hand Sample
Beryl in Thin Section
Thin Section GigaPans
Beryl in plane polars
Beryl in crossed polars