Mammoth and mastodon ivories do not require a permit. Within the United States, wildlife product commerce is regulated on a state and federal level. We will give a review of Federal wildlife law in the following paragraphs. Unfortunately we do not have the space to review individual state wildlife laws. You can ask them about the regulations but have them mail you a copy, then read it.
Wildlife agents are often an incredibly poor source of accurate info.
On the C.I.T.E.S. Endangered Species List. Importing, buying, and selling of African elephant ivory is not allowed internationally. It cannot be imported into or exported out of the U.S. or practically any other country of the world. Legal to sell via an exemption allowing Eskimos to hunt whales and sell baleen crafts. Hippopotamus and Warthog Protected but not endangered.