If you have or collect beautiful things made of ivory, take heed: new rules in the ban on the sale, purchase or donation of anything even partially made of ivory less than 100 years old from African elephants are taking effect in May and June of 2014. It's complicated, but basically, due to an Executive Order passed in February of this year, anyone who wants to trade in ivory must be able to prove in writing that it is more than 100 years old. The law is being enforced in the USA by the U.S. Fish and Wildlife Service. For a complete list of the rules pertaining to the ban, and the effective date, see the U.S. Fish & Wildlife Service web page on ivory, here.
It is important to become informed; for example, it is not illegal to possess legally acquired elephant ivory that was removed from the wild prior to February 26, 1976, but if you want to sell it, or transfer it across state lines in the US, you must obtain something called a CITES pre-convention certificate, which you can only get by proving its age. I told you -- it's complicated. I am not an expert, but these guys are.