Bold linen paper (board), silver leaf, and mineral pigments. Frame size: 39.7 cm (length), 34.7 cm (width), 1 cm (thickness), total weight 660 g. Although often used as a subject in Suiboku-ga (ink painting), this work uses the Japanese painting technique of foiling, with silver leaf applied on the back. The purple irises have a good coloring with the silver background. Nihonga" is based on a style of painting that has existed for more than 1,000 years, and the materials used are old, traditional, and historically cultivated. The technique involves painting on Japanese paper, silk, wood, etc., using natural paints such as sumi ink, iwa-enogu (mineral pigments), gofun (gofun), etc., and glue (nikawawa) as an adhesive. Gold and other metal materials (gold leaf, etc.) are also used. Iwa-enogu, made from ores, is a beautiful, sand-like powder. Mizuhigure, made from clay, is a fine, stretchy, fine-particle paint. Artificial versions of iwa-enogu and mizuhoshi egur are also made, and are available in a wide variety of colors. Goko, made from shells, is a white pigment with fine particles.