I do not really know exactly which mine this is from, it reads Jun Sho Hon Yama Awase
Tosihi, and I firmly believe that it is a close into Kyoto Yamashiro mine from Umigahata.
In any case it is good cutting stone, fairly soft to medium soft and would be good for
chisels or knives. The spots on the surface have within the rings some alternate material
that will fleck out but it is softer in composition than the rest of the stone so it does not
affect the blade in any way.
The tomae strata are the most prevalent in the Kyoto mines, this stone is from one of the
shallower layers called Aka-pin.