It’s will be a sad day in the USA on July 6th, because Order 210 goes into effect which officially bans International commercial import of antique ivory! It also bans almost all interstate trade of ivory unless very strict guidelines are met[ almost impossible to interpret and meet]. For example, if you sell a ivory handled cane within your state to a local buyer , but advertise the sale on the internet it would be consider violating the law—because the advertisement was an interstate act. There are so many confusing criteria regulating the sale of antique ivory [less than 200 grams, 100 years old, de minimis exception, proof of when it was imported, etc] that will have to be tested or challenged by some brave[ or foolish] soul to provide clarity.
The rule with a table describing enforcement and all the criteria for exceptions :