A wide and interesting field for coöperation by metallurgists and archaeologists is the metallographic study of primitive metal work. The present paper is an elementary exposition of techniques which are familiar to every metallurgist but which may be simply applied by archaeologists in any metallurgical laboratory. The typical copper artifacts examined (Plate 11) were kindly given by H. C. Shetrone of the Ohio State Museum, W. C. McKern of the Milwaukee Public Museum, and C. E. Brown of the Wisconsin Archaeological Society. All the specimens are Lake Superior native copper, but they show different kinds of working. Several unworked copper nuggets from the Wisconsin mounds were treated in the laboratory for comparison with the native artifacts.