A field method for the determination of calcium and magnesium in limestone and dolomite

The method is an adaptation of a procedure described by Betz and Noll¹ in 1950. Calcium and magnesium are determined by visual titration using Versene (disodium ethylenediamine tetraacetate) with Murexide (ammonium purpurate) as the indicator for calcium and Eriochrome Black T as the indicator for magnesium.