Usu (mortar)  An usu () is a large Japanese stamp mill with a pestle called "kine" (, ), used to pound rice or millet. While the function of an "usu" is similar to the smaller "suribachi" and "surikogi" mortars, the shape is very different, as the "usu" usually lacks the rough pattern in the bowl, and has a differently shaped pestle which is used in a different manner. The "usu" is usually about one meter high (including pedestal) and has a diameter of ca. 30 cm. The "usu" is usually made of wood or stone. The "kine" is a long wooden mallet with a length exceeding one meter. The "usu" is usually operated by two people at the same time. One person swings the "kine" to pound the rice in a similar motion to chopping wood. It is physically demanding work and is usually done by men who often chant to keep time. Between each swing, another person puts his hand in the bowl to turn the rice. Timing is critical for safe operation of the "usu". The most common use of an "usu" is to pound cooked white rice into a very sticky mass in order to produce "mochi". It is still frequently used in Japan in traditional restaurants and also sometimes in traditional, rural, or wealthier private households. Especially around New Year they are used by companies and organizations to make mochi together and distribute it to the employees to strengthen the group spirit.