铂族元素地球化学标准物质的研制

Preparation of Geochemical Certified Reference Materials for Platinum Group Elements

ＧＰｔ＿１～７系列标准物质由土壤、水系沉积物、富镁超基性岩、富铁超基性岩、含铜镍贫铂矿石及铬铁矿等不同类型７个样品组成。铂族元素的含量范围从土壤和岩石的背景含量到矿石达４～５个数量级。经方差检验样品均匀度良好。标准物质的定值分析采用了不同类型的试金和湿化学法分离富集，以原子吸收、催化比色、催化极谱、等离子体质谱、发射光谱和中子活化等方法进行测定。定值的元素为Ｐｔ、Ｐｄ、Ｏｓ、Ｒｕ、Ｉｒ、Ｒｈ６个铂族元素及Ａｕ。该系列标准物质主要适于作铂族元素地球化学勘查和铂矿勘查中铂族元素分析的量值标准与测试的质量监控。

A set of seven geochemical reference materials for platinum group elements (PGE) and Au including soils, sediments, Mg_rich peridotite, Fe_rich peridotite, poor platinum ores containing copper and nickel, and chromite, were prepared. The contents of PGE in these materials are in differences of 4～5 orders of magnitude from background of soils and rocks to ores. The samples are proved to be homogeneous based on the coefficient of variation of analytical results and variance test and the minimum sampling weight is 10 g (40 g for GPt_6). The fire assay and wet chemical methods were used for sample decomposition and PGE preconcentration. GFAAS, COL, POL, ICP_MS, AES and NAA were used for the determination of PGE. 11 experienced laboratories joined the program. These certified reference materials are mainly used for analysis of PGE in geochemical prospecting, mineral exploration and fundamental geochemistry research.