Emeralds in a pegmatite host rock. Emerald is a variety of beryl, a beryllium aluminium cyclosilicate. Whereas beryl may vary in colour, emeralds alwa

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Emeralds in a pegmatite host rock. Emerald is a variety of beryl, a beryllium aluminium cyclosilicate. Whereas beryl may vary in colour, emeralds always occur in hues of green, thanks to trace amounts of chromium in the composition. When pure and flawless, emerald is the most precious green gemstone known, the deeper the green the more desirable. This specimen, from Takowaja in the Russian Ural, measures 20 centimetres across.

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Size: 3744px × 4859px
Photo credit: © DIRK WIERSMA/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: -, aluminium, beryl, beryllium, chromium, crystal, cyclosilicate, emerald, emeralds, gem, gemstone, geological, geology, green, hexagonal, host, micaschist, mineral, mineralogy, pegmatite, precious, rock