A Novel Method of Archaeological Bronze Identification - Electromagnetic Signatures vs Chemical Composition

Abstract

Bronze metallurgy was a significant step in human technology and civilization as societies evolved from the Neolithic to the Bronze period and acquired the ability to shape different metals into useful tools. The technology to work with copper and bronze was independently developed across the world and, due to different smelting techniques and local ore chemistry, metal ware developed in different regions of the world at various time periods have unique chemical profiles. We previously developed a technique to identify metal alloys based on their stimulated dynamic magnetic signatures. We demonstrated that metals of different chemical composition would exhibit different electrical conductivity, and thus different magnetic field strengths when evoked by different levels of electric current. We further demonstrated that the electromagnetic signatures could be detected by the internal magnetometers located inside most smartphones as a part of the internal compass. In this manuscript we have compiled the electromagnetic signatures and magnetic force vectors of different copper alloys in various electromagnetic fields. The database of signatures are cross-referenced to chemical composition and tensile strength such that one can quickly compare the magnetic signatures of any unknown copper and bronze artifact and arrive at a tentative identity of the metal artifact.