konjō 紺青

A dark blue pigment traditionally derived from azurite or lapis-lazuli *gunjō 群青. A dark color is produced when the mineral is coarsely ground and particles are large. Konjō 金青, mentioned in the Nara period document Shōsōin monjo 正倉院文書 is thought to refer to the same pigment. From the early 18th century, the term konjō was also used to refer to the synthetically produced dark blue pigment Berlin blue *berorin-ai ベロリン藍.