The word "ivory" conjures images of exotic scrimshaw and intricately carved jewelry, figurines and pipes. Evaluators at Pacific City Antiques Gallery say the sources of ivory, both tusk and tooth, are many: walrus, whale, hippopotamus, boar, elephant, mammoth and mastodon. Ivory from African elephants looks warm and tawny. The soft East African variety appears duller than its hard, shiny West African counterpart. Asiatic elephants produce brilliant white, dense, soft and easy-to-carve ivory. Since the institution of worldwide moratoriums in 1989 to protect threatened elephants, ivory prices have soared and fakes abound.
Look for grain with a 15x loupe. Turn a carved piece over and check the bottom -- overlapping grain causes a cross-hatch effect. Ivories always have grain but bone, plastics and resins do not.
Examine the piece with ultra-violet light. Dream Art Gallery in London points out that natural substances like ivory appear lighter under UV light, while artificial and synthetic materials look darker. Fake "ivory" will look darker than it does in regular light.
Test with heat -- the supreme assessment according to both Dream and Pacific galleries -- by using pincers to hold a needle or a nail over an open flame, then placing the red hot tip on the least visible part on the object. The red-hot needle will have almost no effect on the surface of real ivory, other than to leave a tiny mark, but the contact will generate a pungent smell like dental drilling, ivory being the same material as teeth. If the piece is a fake, the hot needle will create a small melt crater and release the unmistakable smell of burning plastic or resin.
Asian art galleries that carry high-end works can appraise carvings and will often supply certificates of authenticity for the pieces they sell.