Watermelon Tourmaline Slice 396922f96d9c151be8082bc5d7a56896 gem quality olivine in a

gem quality olivine in a nickel-iron matrix

Prehistoric Life by Dorling Kindersley

the other being ruby

thereby depriving the wood of oxygen and providing a mineral supply

which gives it the green hue

Watermelon Tourmaline Slice 396922f96d9c151be8082bc5d7a56896 gem quality olivine in aElbaite, also known as Tourmaline, is a group of mixed crystals with the following major members, Elbaite, Dravite, Schorl, Buergerite, Tsilaisite, and Uvite. The general color range of the mineral's family are colorless, pink, green, blue, yellow, brown, and black. What distinguishes tourmalines are the three sided cross sections that are different than any other mineral.