Abstract
A reddish-brown mineral soil discovered at the beginning of the 17th century at Iwami-Ginzan (Omori-cho,
Ota, Shimane Prefecture), registered as a World Heritage Site as an industrial heritage in 2007, was
presented to the Shogunate as a medicinal stone called “MUMYOUI”, and introduced to the general
public. It was manufactured using “elutriation” based on an old document in which the unknown
manufacturing method was written. Elutriation is known generally as a purification method for medicinal
ores, but this elutriation technique was used to produce Red Iron Oxide in the Jomon period, and Mountain
Blue Verdigris, which has been practiced since the Asuka period, It was shown that this iron sand
classification method was also used for “KANNA-NAGASI” in traditional Japanese iron manufacturing, “TATARA”, producing a prosperous slate made in the early Edo period. So, elutriation
was a traditional method shared in the mining industry since ancient times.
