Opal. Close-up of the cut and polished surface of an opal, a type of precious stone. Opal is a form of hydrated, amorphous silica. The glittering irid

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Opal. Close-up of the cut and polished surface of an opal, a type of precious stone. Opal is a form of hydrated, amorphous silica. The glittering iridescent colours of an opal are due to water molecules trapped in the silica structure. This is a Yawah Nut opal, in which the opal (blue) is contained within concentric rings of limonite. It was found in Australia. Magnification: x3 at 4x5 inch size.

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Size: 5083px × 3470px
Photo credit: © DIRK WIERSMA/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: cut, gem, gemstone, geological, geology, hydrated, limonite, mineral, minerals, opal, polished, precious, rock, silica, stone, surface