A rare large cabinet rhodochrosite from the Inakuraishi Mine.  Like most of the Japanese mines that produced specimens, this one is long closed-- it was the site of the largest manganese deposit in Japan and as far as I can tell operated up until the late 1970's.  It seems that today, most Japanese rhodochrosites that one encounters are the botryoidal sort from Oppu, crystalline examples (from anywhere) are considerably rarer as are pieces from this mine.