The term tourmaline is derived from the Singhalese word touramalli , which translates as mixed coloured stones. Tourmaline today is found in a multitude of different variations and colours, which earns the mineral its place as an often rare and valuable gemstone. Tourmaline can be found in all colours of the spectrum, the most notable being the valuable Elbaite variety - which ranges from colourless, to green, pink, and blue. Some individual tourmaline stones may even exhibit more than one visible colour - hence they are termed polychromatic. Tourmalines are also pleochroic - in viewing tourmaline crystals from the axis one will notice that they appear darker, than from the side. Although tourmalines are most popular as gemstones and jewellery, some remain uncut, simply to preserve their natural beauty. Tourmaline crystals are clearly recognisable with their trigonal and prismatic shaping. A distinctive feature of tourmaline is that they are pyroelectric, where the stone will attract dust particles if its surface is rubbed.

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