Here's a new one for you. Boiler Bay sandstone, from one of the sites where I did field work and pretended to study intertidal marine invertebrates and algae. Too much fun to call it work. Anyways, I had been using this for rough work on axes and garden tools and it worked great, but the hardness was too variable. It is mostly soft, but harder in some spots, so it tends to wear very unevenly. Most of this stuff is too soft to be practical, but some harder deposits survive the coastal surf..... this piece was flattened to provide a working face.
Medium grit Aoto waterstones are cut so that the working surface is perpendicular to the primary cleavage plane or layers of deposition, so I took another sample and cut it thus. It seemed to be the right thing to do because the stone works WAY better. The stone composition is more consistent now and even though the stone FEELS really soft, it is surprisingly resistant to dishing. This thing is actually usable, coarse, but somewhat comparable to my "real" Japanese aoto and is a fast cutter. It's got a few scratchy bits that I may try to track down, but it's not a big deal because the scratches are so shallow, they sharpen out quickly.
Easy and fun to use, too soft for small blades but works fine on big chisels and plane blades. Very thirsty and hard to keep wet. Around 600-800 grit? This is the coarsest stone that I have. This Umehiro chisel is pretty hard, but no trouble for this stone.
Soft Arkansas? and diamond nagura.
Mystery slate, no nagura.
Surgical black Arkansas, ODC slurry.
A nice dull mirror finish using the ODC.
I went through the grits pretty fast, not being too fussy. There are still more tools that need sharpening......
Boy, this plain carbon steel is easy. This is from the mystery brown stone.
Bright mirror from the surgical black.
Smoky mirror from the Ozuku asagi. The Sblack made the edge shiny, but the Ozuku made it fine and even.
I really wanted to see how these stones worked on the soft wrought iron used on the plane blades...
This was using the coarse side of the mystery brown stone.
And finished on the top, diamond nagura.
Tools are sharp, for now....
Now how do these stones compare with what I've got, grit-wise? VERY general, just impressions of overall finish and swap-ability. The waterstones are universally faster, but softer and require more maintenance. WAY more expensive (synthetic waterstones aren't TOO expensive, but are such a messy PITA that I only use them on occasion)
Japanese aoto, soft Arkansas?, medium Arkansas?
Mystery slate, mystery brown stone, jyunsyouhonyama.
Inky the mysterious Chinese inkstone/waterstone, surgical black Arkansas.
I'm still looking for an equivalent to the Ozuku asagi. I have been really pleased with this stone, I just wish that it was bigger.
This stuff is soooo fun!