Experts discover traces of rare artificial pigment on Egyptian mummy portraits and panel paintings
The collaboration between the two groups of specialists is part of the Northwestern University-Art Institute of Chicago Center for Scientific Studies in the Arts (NU-ACCESS), where Walton is a senior scientist.
According to art conservator Jane L. Williams, who is employed by the Hearst Museum and a co-author of the study alongside Walton, the findings confirm the distinction between the visual and physical natures of artefacts. The painters manipulated a small palette of pigments, including Egyptian Blue, in order to create a much broader spectrum of colours. Williams had a range of unanswered questions about the paintings concerning the materials and techniques used by the artists. However, Hearst Museum does not have a conservation science division and so working with the scientists from NU-ACCESS has enabled a comprehensive technical survey of the paintings, including the use of the latest technology for non-destructive analysis. A set of analytical techniques, such as such as X-ray fluorescence and X-ray diffraction, allowed the team to uncover the surprising way in which Egyptian Blue was used.
The team have published their findings in the journal Applied Physics A , which is dedicated to materials science and processing. The research is ongoing and will contribute to Ancient Panel Paintings: Examination, Analysis and Research (APPEAR), an international collaborative study project initiated by the J. Paul Getty Museum. APPEAR is aiming to create an international digital database incorporating historic, technical and scientific information on Roman Egyptian portraits.