title: An improved colorimetric determination of vanadium in geochemical prospecting samples.
abstract: The colorimetric method employed by the U.S. Geological Survey for the determination of vanadium in large numbers of geochemical prospecting samples has been examined. Use of sodium hydrogen sulphate for fusing the samples avoids precipitation of potassium phosphotungstate during colour development. Sensitivity and selectivity of the method are enhanced by extracting the phosphotungstovanadic acid into isobutyl methyl ketone.
authors.affiliation: Institute of Geological Sciences Geochemical Division 64-78 Gray's Inn Road London W.C. 1. UK.
authors.forename: J L
authors.initials: JL
authors.lastname: Roberts