Tourmaline is a one of the world’s popular gemstone. It is named of a large group of Boron Silicate minerals. Tourmaline has a Mohs hardness of 7 to 7.5 and that hardness makes its durable sediment granule. It also includes a wide variety of different forms. Tourmaline has a prismatic crystal habit and often has obvious striations that parallel the long axis of crystal. It has a complex chemical composition.