Walrus ivory

Ceremonial ivory masks produced by Yupik in Alaska

Engraved walrus tusk depicting polar bears attacking walrus, dating from the 1940s in Chukotka (Magadan Regional Museum).

Walrus ivory, also known as morse,^[1] comes from two modified upper canines of a walrus. The tusks grow throughout life and may, in the Pacific walrus, attain a length of one metre.^[2] Walrus teeth are commercially carved and traded; the average walrus tooth has a rounded, irregular peg shape and is approximately 5 cm in length.

The tip of a walrus tusk has a tooth 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 (often called osteodentine). Primary dentine has a classical ivory appearance. Secondary dentine is marble or oatmeal-like.

^ Williamson, 9, an archaic term for the animal, but which survived much longer as a term for the ivory, though it too is now old-fashioned.
^ Nasoori, A (2020). "Tusks, the extra-oral teeth". Archives of Oral Biology. 117. doi:10.1016/j.archoralbio.2020.104835. PMID 32668361. S2CID 220585014.

[1] Williamson, 9, an archaic term for the animal, but which survived much longer as a term for the ivory, though it too is now old-fashioned.

[2] Nasoori, A (2020). "Tusks, the extra-oral teeth". Archives of Oral Biology. 117. doi:10.1016/j.archoralbio.2020.104835. PMID 32668361. S2CID 220585014.

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