Atomic-absorption determination of strontium in silicate rocks: a study of major element interferences in the nitrous oxide-acetylene flame

Abstract

A study has been made of the major element interferences associated with the atomic-absorption determination of trace amounts of strontium in silicate rocks by using a nitrous oxide-acetylene flame. Aluminium causes suppression of the strontium signal, while calcium and magnesium act as partial releasing agents, thus reducing the effect of the aluminium. Exact matching of samples and standards can be avoided by the use of lanthanum, which has been shown to be an effective releasing agent in the nitrous oxide-acetylene flame.

Strontium levels in the United States Geological Survey rocks AGV1, BCR1 and GSP1, in the range 244–670 µg g^–1, have been determined with a precision of better than 2 per cent. A spiking and recovery experiment has also been carried out.

Strontium can be measured in silicate rocks with a limit of determination of 0·6 µg g^–1.