Ivory is one of the more traditional materials to use for putting handles or scales on knives and razors. Due to its nature, it is also one of the most controversial materials. Elephant ivory is banned in most places and for a good reason. I don't use it.
However, there is the option of using ivory from fossilized mammoth tusks. That is what I do. Places like Alaska and Canada have a large amount of mammoth tusks in the ground, which can be bought from several sources. At present I use only mammoth ivory from Canadian Ivory Inc.
Any knife or razor I make with Ivory materials will come with a certificate from Canadian Ivory to prove the provenance of their sale to me, and a certificate signed by me as provenance of the handle / scales tracing it back to Canadian Ivory.