Tourmaline Green Rough

From the mines of Paprok in Afghanistan are these beautiful natural tourmaline gemstone crystals.

Sold in lots of 110 carats ($1.80/ct)

Colour:                        Green, blue, pink, yellow, red, purple, orange.

Crystal System:          Hexagonal crystal system

Mineral Family:          Tourmaline.

Chemical Formula:     Al₆B₃Fe₃H₁₀NaO₃₁Si₆

Hardness (Mohs):       7-7.5

Specific Gravity:         3.02-3.26

Refractive Index:        1.616-1.65

Luster:                         Vitreous.

Birthstone:                 Libra

Associated Month:    October