Ear bones have never been my favorite thing. And, that's a good thing 'cause - except for mysticete whale bullae in some locations - ear bones are hard to find. Here's one I've had for a long time.
I have always thought of this as an ear bone of Zygorhiza, an archaeocete whale; but, I have no confirmation of that.
The bone is in three pieces, broken along old cracks judging by the stains. It may have broken in my collecting bag - I don't remember. The broken surfaces reveals a dense, white, glassy material. Anyway, the interior is so surprising, and the cross-section of the bone is so interesting, that I have never glued it back together.
I thought I'd share some images, and maybe someone here will recognize the bone.