Carved Walrus Tusk presented to President William Taft from the Inuit People

This is an example of a diplomatic gift. While ivory from elephants is far more common, ivory from walruses is also protected under CITES. Today, you need a permit to buy, sell, or gift walrus ivory. However, since the gift predates the creation of CITES (and even the Fish & Wildlife Service itself!) it does not require a permit.