Large Bison Buffalo Humerus Bone Fossil Ice Age Partially Petrified Stream Find - Excellent condition, found in local South Dakota stream. A Local South Dakota State professor said these fossils are usually carbon dated 500 to 5000 years old. All my bones and fossils have been sprayed with a clear enamel sealer to help protect and stabilize the material. Heavy item will weigh about 5 pounds with packaging