Microwear Analysis of Prehistoric Stone Tools

Abstract

Archaeologists have used microscopes to study traces of use on the edges of prehistoric stone tools for many years, but the past decade has seen a tremendous increase in the technical sophistication and substantive contributions made by this branch of archaeological research. Our purpose is to summarize the basic approaches archaeologists take to microwear analysis, the potentials of these approaches, and the kinds of traces that microwear analysts examine.Three forms of microwear analysis can be identified and are based on (1) the range of magnification, (2) the type of equipment, and (3) the type of traces examined. The first relies on stereoscopic microscopes, works at magnifications ranging from 10 to 75×, and examines patterns in the abrasion and chipping of tool edges during use. More recent research indicate s that important variation also exists in the way a tool surface is polished during use, and the second analytical approach examines differences in polish appearance as well as utilizing the techniques of the first method. Microwear polishes are visible at magnifications from 100× to 400× using binocular microscopes and incident illumination. Finally, the third approach relies on the scanning electron microscope (SEM) and very high magnifications to identify traces of materials on which the stone tools were used. In this discussion we emphasize the first two of these analytical approaches because very few analysts have used the SEM.