The septa, or gas filled chambers that controlled the buoyancy of this extinct Ammonite during it's life 100 million years ago

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The septa, or gas filled chambers that controlled the buoyancy of this extinct Ammonite during it's life 100 million years ago have been filled with quartz crystals during fossilisation

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Size: 5200px × 3602px
Location: Madagascar
Photo credit: © Nick Greaves / Alamy / Afripics
License: Licensed
Model Released: No

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