Need a little help. I slabbed this today, no bark, good size, 33". Saw dust was very fine, dark, very heavy. I started out at 12/4 and ended up 10/4, to heavy to handle. I'm guessing maybe elm?
The purples and browns in that wood tell me it's black walnut. Also looks some of the sapwood has rotted away, but the heartwood is intact. This matches black walnut also, the heartwood is very resistant to decay.