Tourmaline is a popular gem which is available in a large variety of shapes, sizes and beautiful colours including red, pink, green, blue and brown tones. Bi-colour which displays two separated colours is popular but rare in clean material. Recently mint, teal and blue tones have increased in popularity. Tourmaline is the birthstone for October and the gem for 8th anniversaries, it has a hardness of 7.5 on Mohs scale. Brazil and Afghanistan produce Tourmaline and African countries including Nigeria, Namibia and Kenya, Madagascar and Mozambique are producing small quantities of fine quality Tourmaline although supply can be erratic. Tourmaline is doubly refractive with an RI of 1.619-1.650 and a specific gravity of 3.00-3.20.