花岗岩中钾长石-斜长石相互分选的实验研究

钾长石和斜长石是花岗岩中最主要的造岩矿物,约占岩石中矿物总含量的65%。研究稀有元素在二类长石里的数量分配,是探讨稀有元素存在形式、富集规律、稀有元素与主要造岩元素的相互关系以及稀有元素矿物成因的重要依据之一,也是地球化学研究工作中不可缺少的一环。为了获得纯钾长石和纯斜长石,以往地质工作人员主要寻找岩石中长石斑晶,然后利用钻头和小铁锤逐粒雕取;或用氢氟酸-玫棕试剂染色法把染有红色的钾长石和未染色的斜长石在双目镜下用手工分别挑选。显而易见,用这两种方法每完成一个样品必将花费很多时间,在缺少大斑晶和需要较多数量长石单矿物的情况下,往往会迫使此项研究工作陷于停顿。为了探索长石分选法,作者先后作了优先浮选、静电选、重液分离三个项目的条件实验。鉴于钾长石-斜长石的比重、可浮性、导磁率、导电率都极其相近,是选矿学上较难分选的矿物之一,因此最初的实验都告失败。

THE LABORATORY STUDY OF SEPARATION BETWEEN POTASSIUM FELDSPAR AND PLAGIOCLASE IN GRANITE

This paper was proved by systematic testing datum that the adjusted heavy liguid- centrifugal method is a most effective method for separating potassium feldspar and pla- gioclase,both of which are in granite.The purity of products of two feldspars are 98-- 100%.Tests have shown that the chossing of composition of thoulet solution-distilled water is the very ideal as a dense media.The separating specific gravity of two feldspars is 2.60.It is to establish the processing flowsheet as fllows: Thin section determination-conditioned tests-analysis of conditioned tests-determination of separating specific gravity-separation.