Thread: stone ID

There was a razor hone of considerable repute that was found in the Arbuckle Mountains that was composed of indurated sandstone. The stone was indurated to a depth of 125 ft, but it was the stone on the surface that was the most prized, as weathering had erased the grain of the stone rendering it completely smooth. When you mentioned the lack of grain in your stone, this was the first thing that came to mind. Also, the porousity that you mention is typical of sandstones as well.
Alternatively, based soley on the colouring, it may be a modification of chloritic slate, various hones of this nature can be found all over the world.

Kindest regards,
Alex