陕西金堆城钼矿床中铁钼华的矿物学特征及其意义  

Mineralogical Characteristics of Ferrimolybdite from the Jinduicheng Molybdenum Deposit in Shaanxi Province and Its Significance

作　　者：黄典豪[1] 

机构地区：[1]中国地质科学院矿床地质研究所

出　　处：《岩石矿物学杂志》1989年第4期352-360,共9页Acta Petrologica et Mineralogica

摘　　要：铁钼华产于陕西金堆城斑岩钼矿床的氧化带内,该矿物以往被认为是钼华。笔者对该矿物进行了物理光学性质、化学成分、X射线衍射、穆斯堡尔谱、红外光谱以及失重和差热分析的研究,定名为铁钼华,其分子式为Fe_2(MoO_4)_3·6.8H_2O。同时,将其与国外天然和人工合成的铁钼华作了对比,确定其是在酸性氧化环境中形成的次生矿物。它是原生钼矿床的直接找矿标志。Ferrimolybdite has been found in the oxidized zone of the Jinduicheng porphyry molybdenum deposit, Shaanxi province. The mineral occurs as bundles of fine fibers and encrustations in fissures of weathered rocks and molybdenitebearing quartz veins. In surface exposures, the mineral is associated with quartz, limonite, goethite and jarosite; in hand specimen, it occasionally contains residue of molybdenite and grades into surrounding limontie. The ferrimolybdite has been studied by such means as physical and optical examination, chemical analysis, X-ray diffraction, Mssbauer spectra, IR spectra, TG and DTA. The formula of the mineral is Fe_2(MoO_4_3·6.8H_2O, in which iron is proved to be all in the form of Fe^(3+) by Mssbauer spectra. X-ray diffraction patterns of the mineral are comparable with those of synthetic ferrimolybdite (Kerr, P. F. et al., 1963) but show more reflection lines than other naturally occurring ferrimolybdite.According to geological environment and related mineral association of ferrimolybdite and conditions for forming synthetic ferrimolybdite as well as Titley's experimental results, it is considered that formation and stabi- lity of the mineral are probably contorlled by acid oxidized environment, and the presence of molybdenite and pyrite yields molybdenum and iron necessary to the formation of supergene ferrimolybdite.Although ferrimolybdite fails to form supergene enrichment economic value in this molybdenum deposit, it remains an indicator mineral in search for primary molybdenum deposits.

关 键 词：钼矿床 铁钼华 矿物学 形式条件 

分 类 号：P618.65[天文地球—矿床学]