At a neighborhood garage sale this weekend, I came across this stone in a pile of old tools and junk. I asked the sellers about it and they had no clue of it's origin. For a buck, I snagged it plus a few other odds & ends. It was a dark stone, covered with grime and dust. I rinsed it off and snapped this shot: The stone is 1-7/8" wide and 5.0" long; nearly 3/4" thick at its densest part. It shows wear in the middle section on one side. I brought out my DMT and began lapping and rinsing one side and continued on the sides. This revealed the following: Obviously a double-sided two-grit stone, difficult to distinguish in the original found state. Much greater wear on the coarser side. The coarse side is quite 'coarse' (300?) whereas the smoother side (shown close-up below) feels in the neighborhood of a Norton 1k... The smooth side yields a very thin slurry initially, but with some effort thickens up nicely. So for a buck, I have a new stone. Possibly just a coarse knife or tool combo hone. I don't know if I have anything of practical value with regards to razor honing until I do some side-by-side tests with some other stones. Worst case, I have a new stone to help sharpen my chisels and other tools. Best case: a $1 bevel setter…..
I don't expect this stone to be 'razor-worthy'—although the 1000 grit side may be…..but I'm skeptical. A good knife or tool sharpener, perhaps. It may be very similar to this silica carbide combo stone:
