備前国
The Bizen school is a school that originated in Bizen Province corresponding to present-day Okayama Prefecture. Bizen has been a major production area of high quality iron sand since ancient times. The Ko-bizen school in the mid Heian period was the originator. The Bizen school consisted of schools such as "Ko-bizen, Fukuoka-ichimonji, Osafune," and "Hatakeda".