5.5" Fossil Oyster With Fossil Pearl - Smoky Hill Chalk, Kansas

This is a very nice, fossil pearl from the Smoky Hill Chalk of Gove County, Kansas. It was mounted inside a fossil oyster collected from the same layer of the formation. The pearl is 0.36" wide and the fossil oyster is 5.5" wide. Pearls do not often preserve as they are composted of Aragonite which is not as stable as the calcite of the oyster shell. The pearl itself is a very nice specimen, it's quite large and doesn't display any surface erosion.

The Smoky Hill Chalk Member of the Niobrara Chalk formation is a Cretaceous conservation Lagerstätte, or fossil rich geological formation, known primarily for its exceptionally well-preserved marine reptiles. It outcrops in parts of northwest Kansas, its most famous localities for fossils, and in southeastern Nebraska. Large well-known fossils excavated from the Smoky Hill Chalk include marine reptiles such as plesiosaurs, large bony fish such as Xiphactinus, mosasaurs, flying reptiles or pterosaurs (namely Pteranodon), flightless marine birds such as Hesperornis, and turtles. Many of the most well-known specimens of the marine reptiles were collected by dinosaur hunter Charles H. Sternberg and his son George.