Opal gem and opal rock. Polished and rough specimens of opal, a form of hydrous silicon oxide (silica, SiO2). When cut and polished, it has a distinct

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Opal gem and opal rock. Polished and rough specimens of opal, a form of hydrous silicon oxide (silica, SiO2). When cut and polished, it has a distinctive blue iridescent sheen. The rough specimen comes from Baracoo River, Queensland, Australia.

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Size: 4698px × 3720px
Photo credit: © NATURAL HISTORY MUSEUM, LONDON/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: animal, animatronic, background, baryonyx, biological, biology, cut, cut-, dead, dinosaur, exhibit, extinct, fauna, model, nature, palaeobiology, palaeontological, palaeontology, palaeozoology, paleontological, paleontology, predator, prehistoric, representation, reptile, saurischia, shot, studio, theropod, white, wildlife, zoological, zoology