Fossil sites in Wyoming

American Fossil Quarry and Ulrich's Fossil Gallery are both located in the Kemmerer area and operate on the same basic model: pay a per-person fee, receive tools and instruction, split limestone slabs, and keep whatever fish you recover. Specimens range from small schooling Knightia to complete Diplomystus, Mioplosus, and occasional ray material. The formation dates to approximately 50 million years ago and represents an ancient lake system that preserved fish in extraordinary detail. Both sites are seasonal, typically open May through October.

Kemmerer is 160 kilometers northeast of Salt Lake City and has limited accommodation options. Plan to arrive with supplies and book lodging in advance if you are visiting on a weekend in summer. The altitude sits near 2,100 meters, which affects some visitors. Both quarries welcome collectors of all experience levels and provide on-site guidance for splitting and identifying specimens.