陕西丹凤庙沟铁矿中钪的赋存特征

Occurrence characteristics of scandium in Miaogou iron ore in Danfeng,Shaanxi

陕西丹凤庙沟铁矿为一低品位中型磁铁矿床,赋存于庙沟透辉石岩中,成矿类型为岩浆晚期热液交代铁矿。该铁矿和赋矿岩体均富集有钪,铁矿体钪含量平均达151.03×10^(-6),赋矿岩体钪含量平均达121.17×10^(-6),可考虑回收利用。通过显微镜鉴定、化学多元素分析、电子探针波谱分析及元素面扫描等手段对矿石和赋矿岩石开展岩石学、矿物学和钪元素赋存特征研究。结果表明:矿石和赋矿岩石中均没有钪独立矿物,矿石中的钪以类质同象的形式赋存在阳起石、绿帘石、普通角闪石和磁铁矿中,阳起石中的钪占比达90%以上。赋矿岩石中的钪以类质同象的形式赋存在透辉石、透闪石、磁铁矿和绿泥石中,透辉石中的钪超过90%。矿石中的阳起石是最主要的赋矿矿物,而磁铁矿的钪含量很低,在铁、钪的综合利用中,钪可以从以阳起石为主的铁矿石尾矿中回收。

The Miaogou iron deposit in Danfeng,Shaanxi Province,is a low-grade,medium-sized magnetite deposit hosted in Miaogou diopside rock,and the metallogenic type is a late magmatic hydrothermal metasomatic iron deposit.It is found that both the iron ore and the ore-bearing rock body are rich in scandium,with an average scandium content of 151.03×10-6 in the iron ore body and 121.17×10-6 in the ore-bearing rock body,which can be considered for recycling.The petrology,mineralogy and Sc occurrence characteristics of the ore and ore-bearing rocks were studied by means of microscope identification,chemical multi-element analysis,electron probe spectrum analysis and element surface scanning.The results show that there is no independent Sc mineral in the ore,and all Sc occurs in actinolite,epidote,hornblende and magnetite in the form of isomorphism.The proportion of scandium in actinolite is more than 90%.There are no independent scandium minerals in the host rocks.All scandium occurs in the form of isomorphism in diopside,tremolite,magnetite and chlorite,and more than 90%of scandium occurs in diopside.In the comprehensive utilization of iron and scandium,scandium can be recovered from the tailings of iron ore,which is mainly composed of actinolite.