抄録
The Ebisu iron mine is situated about 7 km., southwest of Mitoya-machi, Shimane Prefecture., The area of the mine is chiefly occupied by quartz diorite, granodiorite and biotite granite., The iron deposits under consideration are found as irregular masses or lenses of magnetite-bearing quartz diorite in the center of a narrow belt of biotite granite., Three types of magnetite are found, (1) idiomorphic magnetite enclosed in other minerals, (2) idiomorphic or hypidiomorphic magnetite filling up the interspaces of quartz and feldspar, and (3) acicular, tabular or xenomorphic magnetite disseminated through rock mass., Of these, the first and the second types are intratelluric, slightly earlier in crystalization stage, than mica, quartz, and feldspar while the last one is later than hedenbergite, garnet, etc., and forms high grade ore., The high grade ore seems to have been formed by secondary pneumatolytic concentration of the early magmatic magnetite.,
