National Treasures & Important Cultural Properties
of National Institutes for Cultural Heritage, Japan

This square box is made of arrowroot, with its corners rounded. It is thought to have originally had an over-lapping lid (kabusebuta-zukuri). Its base (core) is small pieces of arrowroot, which are wrapped and fastened with narrow strips of arrowroot skin. The edges are reinforced with two bamboo strips on both sides, tied with wisteria vines at seven points for each edge. A double-diamond and a four-diamond pattern are woven on each side: the former is on the upper part of a side and the latter is on the lower respectively. The surfaces of both the inner sides and outer ones are lacquered after dying with purplish-red pigment made from su plant (suou). This method is called sekishitsu (lit. red-lacquer). The techniques employed are similar to those seen in the White Arrowroot Box in the Shōsōin Treasures created in the Nara period.