Straight and elongate prismatic crystals of tourmaline of clear green colour embedded in quartz. Tourmaline is a boron-silicate mineral of variable co

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Straight and elongate prismatic crystals of tourmaline of clear green colour embedded in quartz. Tourmaline is a boron-silicate mineral of variable color, some of which are much sought after as semi-precious gemstones. It usually occurs in igneous rocks. Common varieties are elbaite, schorl, opaque and pitch black and dravite, honey-brown and semi translucent. Actual width of specimen is 150 mm.

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Size: 5173px × 3449px
Photo credit: © DIRK WIERSMA/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: boron-silicate, crystalline, crystals, earth, elbaite, gemstone, geology, host-rock, mineral, opaque, prismatic, quartz, science, semi-precious, tourmaline, turmaline