Laser-induced time-resolved luminescence as a means for discrimination of oxidation states of Eu in minerals

Simultaneous detection of divalent and trivalent europium is investigated b y time-resolved laser-induced luminescence in a number of minerals. The sel ectivity of detection is possible by using different time delays after exci tation, different gate widths and different excitation wavenumbers. This te chnique allows detection of Eu luminescence in minerals in which it is hidd en by other luminescence centers in the steady-state luminescence spectra. In such a manner we detected Eu2+ and two different Eu3+ luminescence cente rs in apatite and fluorite, Eu2+ and Eu3+ luminescence in datolite and danb urite, and Eu3+ luminescence in zircon and calcite. (C) 2001 Elsevier Scien ce B.V. All rights reserved.