片へん麻ま岩がんへんまがんMeanings1noungneissmineralogyA high-grade metamorphic rock with distinct banding. Used in geology and mineralogy.この地ち域いきの基き盤ばん岩がんは主おもに片へん麻ま岩がんで構こう成せいされている。The basement rock in this area is mainly composed of gneiss.