this one is the same size as yours 18-20 in. i will post pics when i doIf I didn't know any better, I would rip your arse for stealing my tree :laughing: I seriously have a beech that looks just like that. It's growing near the bottom of a steep bank, next to a spring, very similar to the way your tree is growing. If it were easier to get out i'd have already cut it but where it grows is pushing a mile deep into the forest with no trails or roads and very steep Appalachian terrain. All the trees in there are the original slow growers, just giants. The beech is small, though, around 18" maybe 20.
Post pics when you mill it. I suspect it'll have flame curl all through. I have cut maple & birch that looked similar & it is always deep, broad curls. Pics are a must!!!! Chances are good that whatever created that figure will also have given some color to the wood.