title: Determination of total iron in standard rocks by spectrophotometric titration with EDTA.
abstract: A method for the determination of total iron in silicate rocks is described. It is based on spectrophotometric titration of iron(III) with EDTA after decomposition in a PTFE bomb. No prior separation of interfering elements is needed. The method was tested by analysis of the U.S. Geological Survey reference rocks G-2, AGV-1, GSP-1, BCR-1 and PCC-1. The same sample solutions were also analysed by atomic-absorption spectrophotometry. The agreement with published and recommended values was good.
authors.affiliation: Department of Analytical Chemistry, Abo Akademi, Abo, Finland.
authors.forename: L
authors.initials: L
authors.lastname: Harju
authors.forename: S G
authors.initials: SG
authors.lastname: Huldén