Emerald Diamond Afghani Fashion Gold wedding Jewellery.1026

Emerald Diamond Afghani Fashion Gold wedding Jewellery. 

By Aamir Mannan.
Emerald
For other uses, see Emerald (disambiguation).
Emerald
Emerald crystal muzo colombia.jpg
Emerald crystal from Muzo, Colombia
General
Category Beryl variety
Formula
(repeating unit) Be3Al2(SiO3)6
Crystal symmetry (6/m 2/m 2/m) – Dihexagonal Dipyramidal
Unit cell a = 9.21 Å, c = 9.19 Å; Z = 2
Identification
Formula mass 537.50
Color Green shades to colorless
Crystal habit Massive to well Crystalline
Crystal system Hexagonal (6/m 2/m 2/m) Space group: P6/mсc
Cleavage Imperfect on the [0001]
Fracture Conchoidal
Mohs scale hardness 7.5–8
Luster Vitreous
Streak White
Diaphaneity Transparent to opaque
Specific gravity Average 2.76
Optical properties Uniaxial (-)
Refractive index nω = 1.564–1.595,
nε = 1.568–1.602
Birefringence δ = 0.0040–0.0070