Yusurutsuki is a container for shiromizu (water after washing rice) which is to be used for washing and arranging hair. It was used during the Heian period and after in Japan.
Shiromizu was regarded to be cold by its nature, and combing hair with it was thought to have the effect of calming down people's energy. Tsuki' (the latter part of the word, the kanji used for this word is "坏") means a round-shaped bowl.
The shape of yusurutsuki looks like a teacup with a lid placed on a teacup saucer. It is made of wood, and lacquered and decorated with makie (Japanese lacquer sprinkled with gold or silver powder). Some yusurutsuki were made with gilt bronze or silver, and carved. Yusurutsuki was placed on a platform.
The platform is called "dai" or "shiri." The margins of the platform is 6mm high, and Komon Karanishiki (Chinese brocade) is placed under the bowl. The platform has five legs and about 22.72cm tall, and metallic materials are nailed to the legs. Five straps are made into agemaki (trefoil knots) and attached at the top of each leg. The bottom of the legs are connected to each other like a ring.
Yusurutsuki and the platform are place on the nikai-zushi (a small cupboard with a shelf on top) as interior decoration.
In the "Masasuke Shozoku Sho" (Masasuke's rule book on costumes), an article explaining about furnishings at the hisashi (a long, thin hallway which surrounded the main wing of an aristocrat's home, in traditional Heian architecture) describes about a two-story shelf, 'on the shelf, there is a platform on which yusurutsuki is placed. There is a brocade and the lid of the yusuritsuki on the shelf, and all of them are made by gold."
Also, an article about warawa tenjo (a child of good family placed in court service to learn court etiquette) describes, 'yusurutsuki filled with water should be prepared at 柳.'