Behind the mask − Archaeometric analysis of four gilded Romano-Egyptian mummy masks from the Ny Carlsberg Glyptotek, Copenhagen

• A variety of methods were used for gilding in Romano-Egyptian mummy masks. • SEM-EDS and FTIR identified gypsum and calcite as the main components of the plaster. • Proteomic analysis identified the use of proteinaceous binders for the gilding process. • SEM-EDS characterized the gold leaf as silver-containing gold. This study investigates the materials and production techniques involved in the creation of four gilded mummy masks from Ptolemaic and Roman Egypt from the collections of the Ny Carlsberg Glyptotek, Copenhagen. These masks, dating from the 1st century BCE to the 2nd century CE, are an example of the dual existence of a traditional Egyptian style and newly introduced Roman stylistic elements in funerary art. Various analytical methods, including imaging, FTIR, SEM-EDS, and palaeoproteomic analysis, were employed to identify and examine the composition of the materials. The main constructive material for the masks is plaster made of gypsum and calcite. Red and yellow ochre were used for the preparation layers for the gilding, which was made with silver-containing gold leaf. Four masks is not representative of major developments in gilding techniques, but the study does reveal information about the materials and production techniques available in Roman Egypt.