This ink stick is produced so that the dispersion of carbon particles is constricted to create an overall quiet tone harmonized with lightness in addition to redness (warmth) and white light (grace). The seiboku (blue ink stick) has an overall quiet but warm bluish tone with reddish opaqueness creating the thickness and strength of the color of sumi. As the years go by, the ink stick will grow and its outstanding characteristics will become obvious. Manufactured in 1987.