Arata Koji belongs to the Kasama potters in eastern Japan. In origin the Kasama-yaki was folk craft ware, daily utensils for a farming life. The potters from Kasama took a lot of inspiration from Shigaraki. Kasama came into being during the Anei Era (1772-1781) of the Edo period. Arata Koji uses a blend of Kasama and Shigaraki clays and creates intricate works with geometric patterns that remind of constellations. It is very detailed work that takes about one week to create, from throwing to the final carvings. Arata adds a shibui ("refined") green glaze by compressor and fires for about 30 hours in a gas or electric kiln. He also fires Tenmoku and Shino-esque works (text by Robert Yellin for the Japan Times, March 12, 2003).
Pictures: Portrait of Arata Koji (source article by Robert Yellin); vase with carved decoration (source Artnet); big bowl with wooden box (source Etsy).