A scheme of semi-micro analysis for the major elements in clay minerals, based on modifications to conventional methods of silicate analysis

Abstract

A scheme is presented for the semi-micro analysis for the major elements in clay minerals, based mainly on improvements to conventional colorimetric methods. Silica and alumina are determined after fusing a 50-mg sample with sodium hydroxide. Titanium, total iron, calcium, magnesium, phosphorus and manganese are determined colorimetrically on a hydrofluoric-sulphuric acid digest of a 50-mg sample; sodium and potassium are determined flame photometrically on the same digest. Ferrous iron is determined separately. Additional methods for the determination of total water, total sulphur and fluorine are indicated.