What is Hippo Ivory
Upper and lower canine and incisors are the most common sources for hippo ivory. Each type of tooth has distinctive gross morphology. Close examination of a cross-section of hippo dentine with the aid of a 10X hand lens reveals a tightly packed series of fine concentric lines. These lines can be regularly or irregularly spaced. The orientation of the lines will follow the overall shape of the particular tooth. The center of the tooth may display an interstitial zone (TIZ) . This interstitial zone represents the growth convergence of the developing dentine.
The hippo's curved upper canines are oval to rounded in cross-section. In the uprocessed state, a deep longitudinal indentation extends for the length of the tooth on the inner surface of the curve. A broad longitudinal band of enamel covers approximately two-thirds of the surface area of the tooth. This enamel band is frequently removed during the carving process. The surface which is not coated with enamel displays a very thin layer of cementum. This may also be removed during processing. The interstitial zone in the upper canine is a curved line or broadly arched line.
What is HIPPOPOTAMUS
Historically, hippos have been found throughout all of sub-Saharan Africa. The hippopotamus is typically a slate brown color to muddy brown, with purplish hues often visible. A massive animal, it measures 1500mm in height at the shoulder and has a length of 4310-5160 mm, of which about 560mm is tail. The eyes and nostrils protrude, allowing the animal to see and breathe while otherwise submerged in the water.
Hippopotamus is a valued food source for many of the native people of Africa. The meat is highly prized, as is the large quantity of fat obtained from the kill of a single animal. The hippos teeth are characterized by a thick outer coating of enamel and the fact that they are denser and of finer grain than elephant ivory. Hippos teeth yield superior ivory, and the hide is also considered valuable. Hippopotamus frequently raid agricultural crops. They can inflict a great deal of damage, and inhibit local economies. They are also highly aggressive creatures and have little fear of humans. They are considered among the most dangerous African animals.
(Information from The Animal Diversity Web
http://animaldiversity.ummz.umich.edu/accounts/hippopotamus/h._amphibius$narrative.html)