A "kogo" is a small container used to hold fragrant wood or powder for tea ceremonies and Buddhist rituals. It is also appreciated as a work of art due to its shape, material, and decorations, with some examples of "yamanaka-shikki" lacquerware being particularly famous.
For tea ceremonies, the host and guests enjoy the fragrance of the kogo's contents. Similarly, kogo may be used to burn incense in Buddhist altars as a way of honoring the deceased.
Overall, kogo is an integral part of Japan's traditional culture, with its practical and artistic aspects making it a unique and versatile item to appreciate and utilize.