Some aspects of single-grain luminescence dating

Single-grain methods of luminescence dating have been developed in order to circumvent problems of variability among aliquots of the sample being dated. Sufficient single grains must be separated in order to make an appropriate interpretation of the variability among such grains. We describe an automated apparatus for sorting grains for routine age determinations by green light stimulation. The sorted grains are then available for study of their collective luminescence physics characteristics. Examples are given of statistical frequency functions of grain brightness obtained with the apparatus and their interpretation. These frequency functions are lognormal or similar, covering up to four orders of magnitude, with consequent implications for luminescence dating application.