Not even sure it's a hone, but I just saw a guy put a pretty wicked edge on a pocket knife with one of these, so I'm hoping I could at least set a bevel with one.

Raises no slurry, very soft, porous. Smells like sandstone when wet. Pink and cream colors. I have 12 of them, got the whole lot for $1, so if they are worthless, I'm not out anything really.

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