beech, agreed. I've learned this week - partly from richard - that english sycamore doesn't have those prominent pores (not so much pores, but the dark marks) and looks more like our hard maple over here.
https://i.imgur.com/C6WgYDv.jpg (I could do a guess for money on this piece of wood about whether it's English sycamore or maple, and I think if i took 10% as the house, I'd be the only one who would win in the long term).
It's english sycamore.
If someone so much as farts around beech before it dries, it will mold, spalt or change color one way or another - like that.
But then again, the same is true of the american sycamore here.
I don't know which wood is more poorly behaved but both can be very pretty sawn right.