Origins of Coins and Ancient Metals

A. G. Jackson, Ph.D.

Materials Science and Engineering

Wright State University

Abstract

Coins are used every day for paying for various items we use, but why do we use coins, and from where did the idea come to use metal as a medium of exchange. For at least 2500 years coins have been used by every civilization, and the metals/alloys used have ranged from pure gold, silver, silver/copper, silver/bronze, brass in ancient coins, to nickel alloy, gold alloy, silver/copper and modern brass and bonze in recent coins. From a materials viewpoint, the preparation and fabrication of ancient coins poses some interesting and complex problems, because no definitive record exists of how the various alloys were chosen beyond the simple constraint of availability of the raw ingredients. The appearance of various metals during the third to first millennium BCE influenced which raw materials were used. By the time of the Roman Empire, up to about 400 CE, copper with some silver were the metals of choice for coins for commerce. Compositions varied as the Empire declined and the need for funds to support various wars. Counterfeiting of coins was widespread and workshops for making forgeries were present.

Coins from such a workshop located in Gaul (France) were found and examined in detail in an attempt to identify where in France the workshop was located. The authors (Deraisme and Barrandon) used several approaches including composition analyses to conclude where the workshop was. Extension of their analyses using a different method illustrates the richness in materials science and engineering that such a problem entails. The contribution to this area of study by materials scientists and engineers provides a more firm foundation for conclusions about the materials and allows archaeologists to clarify the context in which metals were used.

Bio of A. G. Jackson, Ph.D.

Dr. Jackson is an Adjunct Professor in the Department of Materials Science and Engineering at Wright State University. He earned a B.Sc. in Physics from Ohio State, the M.Sc. in Physics from the University of Dayton, and the Ph.D. in Metallurgy at University of Cincinnati. His 50 year career has included a number of areas of research, mostly with the U.S. Air Force at Wright Patterson AFB, where he conducted research related to metals of interest for use in engines, mostly Ti alloys. Other areas of research have included characterization of materials using electron microscopy, spectroscopy techniques, x-ray diffraction, modeling of molecular systems, data analysis and pattern recognition in data sets. He has numerous publications and has authored one book on electron microscopy. Dr. Jackson’s latest interests include searching for origins of physical concepts and the study of ancient materials to identify the progression of materials over time.