Heda Stone Quarry 戸田石丁場
This is actually the top side of the stone in the previous picture. The crack runs right through a marking of two overlapping circles, called wachigai. If you look closely, you'll also see another marking on the right edge of this picture. It is a single dot in the middle surrounded by a ring of eight dots. This is often called kuyou. It is the family crest (kamon) of the Hosokawa.