Very consistent. And, I've yet to find any type of beech or HHB that is that color and nearly all heartwood. Not saying it isn't HHB, just saying it has none of the characteristics ours does.
My guess is its an elm of sorts. The heartwood color and bark pattern matches elms up here. But again, its nearly all heartwood in that pic. Those micro leaves seems "off" to me as well. That's a decent sized stump for such tiny leaves.