I was staggered when that Thuri came out of the wash - I had no idea they were ever cut that big for a start. It was clearly a very fine stone, and I assumed might be a Charnley / Idwal / particularly large hard ark.
It had also, happily, been very well looked after by the previous owner; only a couple of quite small chips on the bottom, and hadn't been used with oil - just a bit dirty. Probably the best $5 I'll ever spend!
The Turkish too was interesting... old Turkish stones that will finish a razor well are vanishingly uncommon - most of mine are far better knife stones. This however is a properly good razor stone, which is just as well as it's a bit of a funny size / shape for knives:
Attachment 338943
Attachment 338944