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 chink 1 pound
7 x 8 around the curve by half inch thick. Extremely fine color throughout thickness, including stable deep blues. Solid, minimal delamination or cracking. Could be knife scales, possibly pistol grips, window sanded for scrimshaw etc.
Mammoth ivory chunk 1 pound 12.9 ounces.
12 x 4 around the curve by ½ inches thick. Descent deep natural colors, but has delamination and one big crack issue. Each delamination layer is stable and ¼ inch. Or could possibly restore stabilize to the full thickness if required. Crack takes an even 1 inch off the width. (an inch is a normal need for knife scales.)
Mammoth ivory chunk 1 pound 2 ounces
13 x a tapered 3-2 x about ½ inch thick. Good natural colors, Solid, no soft spots or cracks. Windows could be sanded for scrim or carving, also good knife material.
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.
Mammoth tooth large slice 13.7oz
Nice chunk of solid mamamoth tooth with one side cut and polished. 3 x 2.5 x 2 inches. Lots of uses, sliced for knife scales, carving, just display. This is a close to rock hard material. A band saw with normal wood blade will cut it but after 3-4 slices will be dull. (so about $3 a slice if done this way.) I use a diamond rock saw. Some preparation work has been done I am not calling 'stablized' but cracks filled with glue, mostly on the outside so will not come apart when cutting. Might be fine natural as is or yo may decide to stabilize. This tooth comes from an area carbon dated to 40,000 years old from the interior of Alaska I found myself.