I bought a vintage Yellow Lake stone off eBay from a UK seller. I shaved once with it as a waterstone (despite the box saying Oilstone). Meh. 8kish. I took the razor back to it with oil and shaved this morning. Nice. Darned close to my Thuringian finishes. Coti-level anyway. Better than my mystery blue stone (someone suggested maybe a Yellow Lake), China 12k, Swaty, Nani 12k, and BBW finishes definitely.
It looks like a Dark blue Thuringian with some dark speckles... a lot like the new Mueller stones but without the pyrite.
It looks like a Dark blue Thuringian with some dark speckles... a lot like the new Mueller stones but without the pyrite.