Looks like my green thuri. I think I may have another arriving soon but we will see.This stone had been at my local shop for a while. I had a hunch on what it could be but wasn’t 100% sure. Looking at it cleaned and lapped I am certain it is a thuri rubbing stone. Under magnification they look near identical. The stone on the right is a known Escher View attachment 1462810View attachment 1462811