Routine Determination of Major Constituents in Geologic Samples by Atomic Absorption

Abstract

A method for the determination of Al₂O₃, Fe₂O₃, TiO₂, MnO, CaO, and MgO by atomic absorption is described. A 0.5 to 1.0 g sample is put into solution by treatment with HF, followed by fusion of the HF residue with K₂S₂O_τ and solution of the fused material with HCl. Determination of the various elements is then made using an acetylene—nitrous oxide flame and a premix type burner. The method was developed to eliminate the necessity of changing flame parameters because of the refractory and nonrefractory elements involved. National Bureau of Standards 1-A, G-1, W-1, and U. S. Geological Survey standards BRC-1 and PCC-1 were analyzed by the methods described herein and the results obtained agree within 0.1% or less of the listed values. Standard deviations and coefficients of variation were also calculated for all elements determined on each sample and found to be within acceptable limits.