Purchased as a 'carpenters oilstone'.
Lapped it flat then progressed up to 5k grit sandpaper. Produces medium grey slurry - very smooth with a slightly shiny matt look.
Harder than Thuringian, but not as hard as Llyn Idwal/Charnleys. More slate-like and less dense.
Honing is very slick and produces a good finished edge that is quite smooth Thuringian-like.
Having trouble deciding whether it should come before or after my Thuringian.
Dimensions: 197 x 44 x 12mm
Any ideas for ID? Water of Ayr perhaps? Or Modine's Special Stone? Or the mythical Black Escher?
Similar to a hone Geezer posted about here
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