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Unlike wood charcoal, as found admixed to other cultural remains, ostrich eggshells can be of more direct significance in C-14 dating, especially if they were processed to form, eg, eggshell beads. Normally the time span between laying the egg and working the shell beads is short enough to be negligible for C-14 dating purposes. Another advantage of eggshell dating is that the carbonate of the shell seems to keep exceptionally well over the millennia, whereas, especially in surface sites in a desert environment, organic material such as wood, charcoal or bone protein tends to decompose. With few comparative test samples, we thought ostrich egg samples would yield C-14 dates somewhat too young. The deviation is, however, balanced by performing C-13 analyses and a correction for isotope fractionation of ca 350yr.