My stepdads brother casts bones out of, well i dont know what he casts with, but they are for prostetics, medical training, etc. i have met him a few times, really great guy. anyway he purchased a large box of premium points and blades from a collector and he made up some castings of them from plastic. i dont know what he used for the plastic, but its resemblance to obsidian is awesome. light even passes through it the same way on the edges. i took a picture of the two casts he sent to my step dad and looking at them and handling them is the closest i have been to holding an actual artifact. awesome detail and just a really cool experience. anyway here are the two castings, i took the pics with my moms camera, im not used to it so forgive the angles.
Dustin D