Gemstones

Characteristics of Pyrite

Characteristics of Pyrite: Chemical Name: Iron disulphide Formula: FeS2 Colors: Pale brass-yellow Structure: Cubic Hardness: 6-6.5 Specific Gravity: 5.0-5.2 Refractive Index: 1.81 Lustre: Metallic Streak: Black to brownish-black Locations: Spain,...

Characteristics of Sphalerite

Characteristics of Sphalerite: Chemical Name: Zinc sulphide Formula: ZnS Colors: Yellow-green, red, brown, black Structure: Cubic Hardness: 3.5-4 Specific Gravity: 3.9-4.1 Refractive Index: 2.36-2.37 Lustre: Resinous to adamantine Streak: Brownish...

Characteristics of Sapphire

Characteristics of Sapphire: Chemical Name: Aluminum oxide Formula: Al2O3 Colors: Most colors Structure: Hexagonal, trigonal Hardness: 9 Specific Gravity: 4.0-4.1 Refractive Index: 1.76-1.77 Lustre: Adamantine to vitreous Streak: Colorless Locations:...

Characteristics of Ruby

Characteristics of Ruby: Chemical Name: Aluminum oxide Formula: Al2O3 Colors: Red Structure: Trigonal Hardness: 9 Specific Gravity: 4.0-4.1 Refractive Index: 1.76-1.78 Lustre: Vitreous Streak: Colorless Locations: Myanmar, Sri Lanka, Nigeria,...

Characteristics of Spinel

Characteristics of Spinel: Chemical Name: Magnesium aluminum oxide Formula: MgAl2O4 Colors: Red, yellow, orange, red, blue, green, black, colorless Structure: Cubic Hardness: 8 Specific Gravity: 3.6 Refractive Index: 1.71-1.73 Lustre:...

Characteristics of Chrysoberyl

Characteristics of Chrysoberyl: Chemical Name: Beryllium aluminum oxide Formula: BeAl2O4 Colors: Green, yellow, brown Structure: Orthorhombic Hardness: 8.5 Specific Gravity: 3.7 Refractive Index: 1.74-1.76 Lustre: Vitreous Streak: White Locations: Russia,...