各化学元素在地壳中的平均含量值为该元素的“克拉克值”,亦称为“地壳的元素丰度”。近年来将化学元素在各种矿物中的平均含量值称为各化学元素的“矿物克拉克值”(矿物的元素丰度)。这种“矿物克拉克值”对于某些金属矿产的地质找矿工作具有一定的实际意义。根据大量分析数据的统计,某些希有金属、分散元素之几种重要的金属矿物和造岩矿物中 The average content of each chemical element in the crust is the “Clarke value” of the element, also known as “the elemental abundance of the crust.” In recent years, the average content of chemical elements in various minerals is called the “mineral Clarke value” (the elemental abundance of minerals) of each chemical element. This kind of “mineral Clarke value” is of some practical significance for the geological prospecting of some metal ores. According to the statistics of a large number of analytical data, some of the most important metallogenic minerals and rock-forming minerals that are expected to have metals and dispersed elements