Dinosaur fossil T-Rex Knee bone. Astragalus (adult) this small bone is found in the back leg inside the knee joint of the great Dinosaur T-Rex, Very rare to find this fossil, Very few of these small bones recovered, This was found ten years ago in east Montana on private land with owners permission, This is your chance to own this very rare, hard to find Tyrannosaurus. The great Lizard, Astragalus (Adult) knee bone fossil. The item "Dinosaur fossil T-Rex Knee bone, (Astragalus Adult).Tyrannosaurus" is in sale since Friday, July 30, 2021. This item is in the category "Collectibles\Rocks, Fossils & Minerals\Fossils\Vertebrates\Amphibian, Reptile & Dinosaur". The seller is "fron10" and is located in Thonotosassa, Florida. This item can be shipped worldwide.