A deep purple — described both as an indigo-toned deep purple and a purple-toned deep indigo. Also written "紫根" (shikon, "purple root") because it was dyed with the roots of purple gromwell (Lithospermum erythrorhizon). Though the color name came into use after the Meiji period and is not particularly ancient, it is highly esteemed. It is used in the Emperor's enthronement ceremony, and the championship flag of the spring high school baseball tournament is this color.