Found a hip bone replacement in my new car?

I bought a car the other day for $500. Upon later inspection, I found what appears to be a stainless steel hip bone replacement. There is a serial number and manufacturer on it. I'm a little stumped on what to do. I can not get a hold of the lady I bought it from. Now could this be worth any money? Should I sell it, make it into my shifter knob, throw it out?