Gemstones

Characteristics of Kornerupine

Characteristics of Kornerupine: Chemical Name: Magnesium aluminum borosilicate Formula: (Mg,Fe2+) 4(Al,Fe3+) 6(SiO 4,BO 4) 5(O,OH) 2  Colors: Green, white, blue Structure: Orthorhombic Hardness: 6.5-7 Specific Gravity: 3.3-3.5 Refractive Index: 1.66-1.69 Lustre: Vitreous Streak: White Locations: Madagascar,...

Characteristics of Epidote

Characteristics of Epidote: Chemical Name: Calcium aluminum ferro silicate Formula: (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH)  Colors: Pistachio, mottled pink and green (unakite) Structure: Monoclinic Hardness: 6-7 Specific Gravity: 3.3-3.5 Refractive Index: 1.73-1.77 Lustre: Vitreous...

Characteristics of Vesuvianite

Characteristics of Vesuvianite: Chemical Name: Calcium- iron- magnesium aluminosilicate Formula: Ca10Mg2Al4(SiO4)5(Si2O7)2(OH)4  Colors: Yellow, brown, green, red, black, blue, purple Structure: Tetragonal or monoclinic Hardness: 6.5 Specific Gravity: 3.3-3.4 Refractive Index:...

Characteristics of Axinite

Characteristics of Axinite: Chemical Name: Calcium- iron- manganese- aluminum boron silicate Formula: Ca4Fe2+2Al4[B2Si8O30](OH)  Colors: various Structure: Triclinic Hardness: 6.5-7.0 Specific Gravity: 3.2-3.3 Refractive Index: 1.67-1.70 Lustre: Vitreous Streak: Colorless to...

Characteristics of Danburite

Characteristics of Danburite: Chemical Name: Calcium boron silicate Formula: CaB2(SiO4)2 Colors: Colorless, yellow, pink, yellow-brown Structure: Orthorhombic Hardness: 7-7.5 Specific Gravity: 3 Refractive Index: 1.63-1.64 Lustre: Vitreous to greasy Streak:...

Characteristics of Beryl

Characteristics of Beryl: Chemical Name: Beryllium aluminum silicate Formula: Be3Al2Si6O18 Colors: Colorless, red, blue, green, yellow Structure: Hexagonal Hardness: 7.5-8 Specific Gravity: 2.6-2.8 Refractive Index: 1.57-1.60 Lustre: Vitreous Streak: White...