Approximately 145 to 66 million years ago, the Cretaceous Sea covered a large portion of New Mexico. While fairly shallow, it was filled with marine life. Sharks swam the inland sea. Giant clams burrowed in the mud. Dinosaurs roamed the shores and pterosaurs flew the skies....but I digress.
Collected in northwest New Mexico, at an elevation of about 6500 feet, these little fossil shells once housed creatures that were part of the life in that long-ago sea.