Tusks or teeth of mammals, especially those from elephants, walrus, hippopotamus, and whale; or the smooth, hard, yellowish-white material of which they consist; or a thing made of ivory.

May also refer to the color of ivory, a pale grayish yellow to yellowish white. Because so many tusk producing animals are endangered species, it is unethical to purchase, use, or sell contemporary ivory. There are synthetic materials which appear nearly identical to ivory.  (Artlex.com)

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