鹿児島県屋久島仁田鉱山産 ferritungstite

概要

論文の詳細を見る
Average of seven microprobe analyses of ferritungstite from the Nita mine, Yaku Island, Kagoshima Prefecture, gave : CaO 0.51,Al_2O_3 1.10,Fe_2O_3 6.10,WO_3 80.10,MoO_3 0.19,total 88.00wt%. The low total is ascribed to H_2O. The empirical formula is : Ca_<0.04>(W^<6+>_<1.55>Mo^<6+>_<0.01>Fe^<3+>_<0.34>Al_<0.10>)_<Σ2.00>(O_<4.76>(OH)_<1.24>)_<Σ6.00>・2.38 H_2O (basis : (W+Mo+Fe+Al)=2). If Ca is dropped, the ideal formula is derived as W^<6+>Fe^<3+>O_9(OH)_3・nH_2O, where n∿5. X-ray powder pattern is indexed on a cubic face-centered cell with a=10.288A, Z=4 [W^<6+>_3Fe^<3+>O_9(OH)_3・∿5H_2O], substantiating the conclusion of ERCIT & ROBINSON (1988), who indicated ferritungstite to be a pyrochlore type compound with an A-site deficit, which is more remarkable in the present material.
国立科学博物館の論文
1994-06-22