It is real tortoiseshell and is legal to buy and sell in the US because it’s an antique. I don’t know if it could be shipped out of the country. New tortoiseshell from a turtle is illegal to buy or sell. Tortoise was super popular for the second year of mourning in Victorian times when all black all day was allowed to be relieved by brown lol. They made grief into a hobby. I have a cuff bracelet that I got in England and another locket on a tortoise watch chain that I found at an estate sale in need of tlc (baby oil perked it up).
Buying elephant ivory depends on what state you live in. In all, new elephant ivory is rightly banned. In most, antique ivory is legal to buy and sell, but in some like CA and NY it is illegal to buy ivory of any age...although not to own so if you moved there owning family pieces or something it’s ok. I have a couple small ivory roses that were my grandmother’s and a pendant that is antique that I bought. I say elephant ivory because there is also mammoth ivory, which I own, that falls into a weird area of being colored with the all ivory is bad brush even though it’s from an extinct animal and yet is legal to sell unless your state banned all ivory. Native Alaskans carve it as a business, which is where mine came from. My avatar is my elephant carved of mammoth ivory based on a pendant in a book I became obsessed with as a kid. Not sure where you live, but Britain is soon to ban all buying and selling of any ivory hoping to make it worthless to stop poaching...
Both are tricky because you have to know your state’s laws, know you aren’t buying modern pieces using newly killed animals vs antiques made before bans, and know you aren’t paying the price of real and buying faux as both substances have always had look a likes (tortoise objects were faked with celluloid, bakelite and horn back in the day, now with plastic) (ivory mimics are bone, tauga nut and celluoid).