Occasionally, in arid areas in/near copper deposits, animals perish and therir bones are replaced by copper minerals from the water running through the veins and cracks in the rocks over thousands of years - a phenomenon known from a few places around the world. Here, in this case the replacement is by turquoise of carving grade! This rare pseudomorph of turquoise after bone (odontolite) exhibits a pleasing light teal-blue color. It is apparently the jawbone of a mammal, probably dated around 20-40,000 years old. Unusual and dramatic! Complete all around, this is a phenomenally good example of this rare oddity. Ex. Ken Roberts' well known pseudomorph collection.