Walrus tusk ivory comes from two modified upper canines. The tusks of a Pacific walrus may attain a length of one meter. Walrus teeth are also commercially carved and traded. The average walrus tooth has a rounded, irregular peg shape and is approximately 5cm in length. Binomial name Odobenus rosmarus (Linnaeus, 1758) Subspecies Walruses are large semi-aquatic mammals that live in the cold Arctic seas of the Northern Hemisphere. ... Ivory is a hard, white, opaque substance that is the bulk of the teeth and tusks of animals such as the elephant, hippopotamus, walrus, mammoth, etc. ... The metre is the basic unit of length in the International System of Units (SI: Système International dUnités). ...

Pacific Walrus at Cape Peirce

The tip of a walrus tusk has an enamel coating which is worn away during the animal's youth. Fine longitudinal cracks, which appear as radial cracks in cross-section, originate in the cementum and penetrate the dentine. These cracks can be seen throughout the length of the tusk. Whole cross-sections of walrus tusks are generally oval with widely spaced indentations. The dentine is composed of two types: primary dentine and secondary dentine (often called osteodentine). Primary dentine has a classical ivory appearance. Secondary dentine looks marble or oatmeal-like. Public Domain U.S.Fish & Wildlife Service Pacific Walrus at Cape Peirce http://images. ... Public Domain U.S.Fish & Wildlife Service Pacific Walrus at Cape Peirce http://images. ... Tooth enamel is the most highly mineralized and hardest substance of the body . ...

Folk art of walrus ivory carving has been popular in Russia since Middle Ages. Notable schools of walrus ivory carving have been developed in Kholmogory and Tobolsk. Kholmogory (Холмого́ры) is a village in Arkhangelsk Oblast, Russia. ... Tobolsk (Тобо́льск; Tatar: Tubıl) is a town in Tyumen Oblast, Siberia, Russia. ...