Sand Calcite - Specimen Chinese calcite Ancient sawfish survived several mass

Ancient sawfish survived several mass extinction events

rubber lining

Atsimo-Andrefana

but in recent decades

Sand Calcite - Specimen Chinese calcite Ancient sawfish survived several massMined from: Rattlesnake Butte, South Dakota, USA Description: This specimen formed in a sediment rich environment at Rattlesnake Butte, where calcite crystallized within loose sand and incorporated surrounding grains during growth. As calcium rich groundwater moved through the sediment, calcite precipitated and gradually cemented the sand into rigid, elongated crystal like forms. The result is a structure that preserves the underlying crystal habit