Unusual appearance of Schreger-like pattern in Hippopotamus amphibius ivory: wildlife forensics investigation of a netsuke

Abstract

The National Fish and Wildlife Forensics Laboratory routinely receives confiscated wildlife parts and products (including ivory) for identification purposes as part of wildlife law enforcement casework. Identification of evidentiary ivory typically involves a detailed and comprehensive visual and microscopic examination of the objects, as well as observation with ultraviolet light. Of thousands of ivory objects examined at the Lab, the author has observed unusual non-Proboscidean (elephant) objects with Schreger-like (cross-hatched) pattern. One of these objects was a small well-polished netsuke carved from a hippopotamus canine.