A general term for blue-green garden stones. In most cases, they are green schist. According to their area of production, they are called Kishu aoishi, Awa aoishi, Iyo aoishi, etc. They are used in stone arrangements or as the mirror stone of a dry waterfall.
Japanese Garden Dictionary: A Glossary for Japanese Gardens and Their History
(C) 2010 by Ono Kenkichi and Walter Edwards. All rights reserved.