The developing field of petrology in archaeology

This paper traces the development of optical petrology, noting the fields in which it can profitably be employed and what its limitations are. It then discusses the principles behind the use of trace element analysis. Variants of optical emission spectrometry, atomic absorption spectrometry, X-ray fluorescence spectrometry and neutron activation analysis are described and compared in terms of expense, analytical accuracy and possible destruction of the sample, illustrated by some recent attempts to source artifacts of obsidian, flint, sanukite and soapstone.