I live next to Penrhyn Quarry and hang out (with a bloke who has all the tools) in Cwmorthin Slate Mine all the time, so I could try to find something and cut it to size. But when my father had been rummaging around in the garden he mentiooned there had been a seating are in a strange corner; there was slate on the floor. I had noticed a standy-uppy slab (57 x 122 cm so not even big enough for the roof of the T) but I had not really paid attention to the slate on the floor. But maybe it would be worth it! So one day I did. And I pulled out what clearly had been a hearth! Two big slabs, 46 x 122, with an elegant round corner cut out and two holes on the other side. Altogether these slabs should do! And I'm sure they are local slate.
The overgrown seating area; one slab is removed but you can't even tell
The two removed slabs standing ready