I cut this bone at the point where it connects to the breast-bone. It thins out, then gets thicker. I can cut it anywhere along the length, and I'll find the same consistency.
I had three German volunteer workers with me when I found out about the bones being ivory. Cut them in several ways for the volunteers to make trinkets, for the same results. It's a solid plasticky (for want of a better descriptor) substance.
Most bones I've handled are brittle, and hardened externally, with a softer centre. This substance is not like that at all. The closest un-natural substance I could equate this with for comparison, would be a nylon breadboard. Though not so white, of course. And a bit harder, but not brittle.
Would like to send you a sample.
Wonder if that's possible??