Analyses of copper- and beeswax-containing green paint on Egyptian antiquities

Four samples of waxy, green paint from ancient Egyptian objects have been examined. Analysis was performed using infrared and X-ray fluorescence spectroscopy. Each sample was found to contain beeswax and copper. An apparently identical paint could be made by heating together copper and beeswax at 110°C or by mixing copper(II) acetate with molten beeswax. The copper salts of various palmitic and stearic acids were made and their infrared spectra obtained, which led to the conclusion that the green paint contained copper salts of beeswax fatty acids.