島根・鳥取・岡山・広島県境地域の超塩基性岩に伴う鉱物の研究 : 岡山県高瀬鉱山産の加水ザクロ石およびクロム鉄鉱

A new hydrogrossular generated in aluminum pyroxenite which have undergone metasomatic metamorphism involving the addition of alumina and lime and the subtraction of magnesia is found from the Shinguchi level of the Takase mine, Okayama pref. It is considered that the aluminum pyroxenite originated from pyroxenite pocket in peridotite mantle was derived as xenolith in ultrabasic rock - harzburgite. Optical, chemical and powder x-ray data of the hydrogrossular are given and the formula is described. Two kind of chromites was investigated by chemical and x-ray powder photograph method. These data are give.n in table. The chromites is said as aluminian chromite rather than chromian spinel. The origin of the chromites are mentioned in the paper.