Most materials I find or make myself. I sell a variety of materials for making knife handles. I make knives myself and am always seeking interesting handle material. You might look all around the web site at various raw materials. But some material I cut with the knife maker in mind, that I know will work and has been cut specifically for knife makers. Most of the wood under 'raw wood' is good for knives as well, but here are some materials to glance through all in one place. Most of these materials I find or create myself so can answer questions on suitability use care etc..
Mammoth ivory chunk 1 pound 12.9 ounces.
Mammoth ivory chunk 1 pound 2 ounces
Mammoth tooth slice set 6.6 ounces
Set of mammoth tooth slices traditionaly sold for knife handle scales but could have other uses. 2 x 3 inches, 1/4 inch thick. Almost rock hard but can be worked with belt sander, normal cutting tools- just hard on tools if it's not rock equipment. These are all natural slices in dyed ungtreated. Could possibly get two knife scale sets. I would not choose this as scrimshaw material as there is alternating harder and softer layers. Wonderful colors, rare unique material.