Gemstones

Characteristics of Diaspore

Characteristics of Diaspore: Chemical Name: Hydrous aluminum oxide Formula: AIO(OH) Colors: White, yellow, lilac, pink Structure: Orthorhombic Hardness: 6.5-7 Specific Gravity: 3.3-3.4 Refractive Index: 1.70-1.75 Lustre: Vitreous Streak: White Locations:...

Characteristics of Rutile

Characteristics of Rutile: Chemical Name: Titanium dioxide Formula: TiO2 Colors: Reddish brown to red, golden Structure: Tetragonal Hardness: 6-6.5 Specific Gravity: 4.2-4.3 Refractive Index: 2.62-2.90 Lustre: Sub-adamantine to sub-metallic Streak:...

Characteristics of Cuprite

Characteristics of Cuprite: Chemical Name: Copper oxide Formula: Cu2O Colors: Shades of red to nearly black Structure: Cubic Hardness: 3.5-4 Specific Gravity: 6.1 Refractive Index: 2.85 Lustre: Adamantine, submetallic Streak:...

Characteristics of Cassiterite

Characteristics of Cassiterite: Chemical Name: Tin oxide Formula: SnO2 Colors: Medium to dark brown Structure: Tetragonal Hardness: 6-7 Specific Gravity: 6.7-7.1 Refractive Index: 2.0-2.1 Lustre: Adamantine to metallic Streak: White,...

Characteristics of Taaffeite

Characteristics of Taaffeite: Chemical Name: Beryllium, magnesium, and aluminum oxide Formula: BeMg3Al8O16 Colors: Pale mauve, green, sapphire blue Structure: Hexagonal Hardness: 8-8.5 Specific Gravity: 3.6-3.62 Refractive Index: 1.71-1.73 Lustre: Vitreous...

Characteristics of Hematite

Characteristics of Hematite: Chemical Name: Iron oxide Formula: Fe2O3 Colors: Black, grey, silver, red, brown Structure: Trigonal Hardness: 5.5-6.5 Specific Gravity: 5.1-5.3 Refractive Index: 2.94-3.22 Lustre: Metallic to earthy Streak:...