Double-chambered Blue Bed thunder egg agate agate. Agate is an aggregate of different forms of silica (SiO2) that have formed concentric bands within

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Double-chambered Blue Bed thunder egg agate agate. Agate is an aggregate of different forms of silica (SiO2) that have formed concentric bands within a geode. A geode forms when the silica precipitates from liquid onto the inside surface of an empty pocket in a host rock.

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Size: 4761px × 3671px
Photo credit: © NATURAL HISTORY MUSEUM, LONDON/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 1800s, 1873, 19th, america, american, bahia, black, boat, boats, brazil, century, challenger, coast, coastal, coastline, harbor, harbour, landscape, monochrome, port, south, town, voyage, white