釈迦内鉱山第一鉱体の鉱石
1966 年 82 巻 944 号 p. 1031-1038
詳細
1966 年 82 巻 944 号 p. 1031-1038
The Daiichi ore-deposits of the Shakanai Mine are of the “Kuroko” type, having a zonal arrangement of Kuroko (black ore), bko (yellow ore), siliceous ore and gypsum ore.
The Kuroko is classified into three types, fine grained compact Kuroko, coarse grained Kuroko and breccia-like Kuroka. Galena, grey copper minerals and colloform texture in pyrite are characteristic in fine grained compact Kuroko. Conversely, they are seldom observed in coarse grained Kuroko. Breccia-like Kuroki5 is composed of fragments of ores and clayey matrix. The mode of occurence of it is very interesting. Main ore minerals in Oko, siliceous ore and gypsum ore are pyrite and chalcopyrite, of which grain sizes are, generally, large, and in which colloform texture is seldom found.
It is surmised from microscopical observation and chemical analyses of the ores, that the grey copper minerals range from tetrahedrite to tennantite, and that the tetrahedrite mainly bears silver.
