Dolphin that has been cut and polished.Undetermined Genus & Species.Late Miocene (Tongaporutuan)Wanganui River, Taumarunui, King County.Central North Island.New Zealand.

Interesting piece! Looks like very hard rock. Was there much more of the concretion there?

Reminds me of the "Visible Human Project" They froze a human body in a block of ice and cut it in thin sections and photographed each one. You then get a virtual CAT Scan of the body.

THanks Doctor Mud yes,the rock is very hard and i don t know if there were more of the concretion,it came from an exchange with an Oz friend