Investigations concerning the concentration of minor ele ments (Co, Ni, Mn, As) in pyrites and cube-edge measurements were carried out on thirty-nine specimens taken from the Chichibu mine (26 samples), the Taishu mine (7 samples), and the Ashio mine (6 samples), by using X-ray fluorescent method as well as X-ray diffraction method. The results obtained are as follows;

No abstract

In sulphide deposits, generally, various sulphide minerals occur in massive or crystalline aggregates showing the relations of int imate paragenesis, and these minerals usually contain small amounts of selenium as their minor constituents. It is a significant subject from a view point of economic geology to clarify the relations between the selenium content in various sulphide minerals which exist in the sulphide deposits and their mode of occurrence. In present work, as a portion of these problems, the manner of dist ribution of selenium in several sulphide minerals which co-exist in one hand specimen and show the relations of intimate paragenesis was mainly studied. And furthermore, it was examined whether selenium distribution in given minerals can or cannot be utilized as a geological thermometer when the formation-temperatures of minerals should be discussed.