Natural Sharpening Stones
Natural sharpening stones are geological miracles resulting from some two million years of tectonic movement. Since the dawn of man, humans have relied on stones to make edged and pointed tools. Prehistoric prototypes of sharpening stones already existed by the Yayoi period (as early as 300 B.C.). It is no coincidence that regions known from ancient times for their fine sharpening stones also became centers of production for exquisite tools, arts and crafts.