This is a fossil land tortoise spur (Hesperotestudo sp.) that is still fused to the bone. From what I am told, these are pretty rare, and my experience seems to support this since this is the only one I have recovered. This piece is quite weathered, but is complete. This specimen was recovered from the Peace River, Bone Valley Formation, Hawthorn Group, Florida. This area has rich deposits of fossils from the Miocene, Pliocene, and Pleistocene periods (approx. 11,000 to 23,000,000+ years ago).
Refer to the photo. The black centimeter cube is shown for scale and is not included. You are purchasing the specimen shown.