礦物資料庫與水晶療法礦物Písekite-(Y)Písekite-(Y)(Y,As,Ca,Fe,U)(Nb,Ti,Ta)O4 root IMA questionable成分Composizione (% in peso)NbYONbNiobium37.8%YYttrium36.2%OOxygen26.0%次要脈輪third eye