The statue of Karomama, a testimony of the skill of Egyptian metallurgists in polychrome bronze statuary

The statue of Karomama, Divine Adoratress of Amon during the XXII° Dynasty, is one of the masterpieces of the Department of Egyptian Antiquities, Louvre Museum. It has been recently restored, for the first time since the restoration by Alfred André done in 1896. That operation led to a description of the circumstances of the former restoration. It allowed to better understanding, through the detailed examination of the decoration, the techniques of polychromy on bronze pieces of art, as they were practiced by Egyptian metallurgist craftsmen. A comprehensive laboratory characterization of the different parts of the statue has been performed: X-ray radiography to evidence the mode of casting of the statue itself, of the assembled parts as the arms and the wig and of the base; analyses by non-destructive ion beam techniques on the particle accelerator AGLAE of the various inlays present on the statue and on the base. The results show an impressive juxtaposition of various metal alloys (gold, gold-silver and gold-copper) used to obtain a polychrome effect. The detailed examination and the analyses have evidenced for the first time the presence of an intentional patina on the inlays present in the wing quills of the statue and on the inlaid hieroglyphs of the base. This black patina, referred in the Egyptian texts as Hmty-km, was in general observed as a background on the Egyptian objects but is here reported for the first time on inlays. It is moreover demonstrated that several copper-gold alloys and perhaps several recipes are used to obtain a blackish coloration on various copper-gold alloys. Those observations are discussed in view of the existing literature about “black bronzes” or “black copper”.