Study of paramagnetic and luminescence centers of microcline feldspar

Microcline feldspar crystal has been analyzed in order to determine the centers suitable for use in ESR and luminescence dating. ESR measurements at RT showed the Fe3+ line, and at 77 K the Si–O−..X signal with g=2.0052, 2.0098 and 2.0128. TL glow peak at 157 and 300 °C in UV interval were observed and in the VIS range we noted peaks at 150, 280 and 340 °C. TL growth curve of the 340 °C peak could be fitted by a saturating exponential equation and can be used in TL dating. Emission curves showed band widths 1.95±0.09, 2.73±0.08 and 4.94±0.50 eV. Transitions from 4T1→6A1 of Fe3+ can be associated with the 1.95 eV band and the transition from 4A1 4E(G)→6A1(S) with 2.73 eV band.