Brazilian Blue-Green Tourmaline Oval Cabochon

About Tourmaline

Tourmaline is a family of boron-bearing minerals whose crystals are usually long and strongly striated. It occurs in almost every colour, from black schorl and vivid green verdelite to pink, red, blue and colourless material. A single crystal may show more than one colour, producing watermelon or bi-coloured tourmaline. Transparency ranges from opaque to transparent; fine gem material is valued for its lively colour and…