title: Age Determination by X-ray Fluorescence Rubidium-Strontium Ratio Measurement in Lepidolite.
abstract: X-ray fluorescence analysis of several lepidolites whose rubidium and strontium concentrations had already been determined by neutron activation and stable isotope dilution, or both, indicates that this technique can be used for rapid nondestructive reconnaissance rubidiumstrontium studies, and that an x-ray analysis method comparable in accuracy to isotope dilution can probably be developed for dating Precambrian lepidolites, as the simple technique presently used has many obvious possibilities for improvement.
authors.forename: L F
authors.initials: LF
authors.lastname: Herzog