Is all ivory the same

Factual Questions
1

I understand Ivory can come from elephants, or walruses or even old dead mammoths.

Is all ivory the same chemically? Is it just basically teeth?

2

They’re all basically exactly the same. Though I believe there are physical ways to tell between an elephant tusk and a mammoth tusk, for instance.

3

According to Ann Carlson, of San Francisco State University’s Museum Studies Program:

"Ivory, bone, teeth, and antler have very similar chemical components. They are comprised of 50%-70% minerals, mainly calcium phosphate with small amounts of calcium carbonate, calcium fluoride, and magnesium phosphate.

Elephant and mammoth tusks are the only TRUE sources of ivory. Narwhal tusks, hippopotamus teeth, and walrus tusks are considered ivory-like materials. They differ primarily because they are harder and more brittle than true ivory. "
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