The metal of the moon goddess

摘要

Arsenical copper was widely used in the Early Bronze Age, but it was not employed after the introduction of copper-tin alloys in the period around the Middle Bronze Age. Nevertheless the present research showed that a few ornamental objects of particular kind were made of a copper alloy with a silvery surface, containing arsenic, antimony and often some cobalt and nickel still in the Final Bronze Age and in the Iron Age. This alloy is very fragile and can only be cast, it is very difficult to cut and file and shows a characteristic silvery surface. The shiny and silvery grey colour of these objects is due to a segregation phenomenon. During the slow cooling of the metal the As rich a and y compound (eutectic) is pushed to the surface through feeders which look like filaments running into the metal body and forms the typical silvery grey layer. The microstructure of the eutectic shows a solid solution phase a and a Compound y, containing 29 X 65 As (Cu_3As). The eutectic can develop already with 1-2 percent of As in the alloy. Ornamental objects made of this distinctive and beautiful material were worn by women who had special powers and exceptional functions in the society of the time and were connected with the cult of the moon and fertility goddess.