Combining multispectral images with X-ray fluorescence to quantify the distribution of pigments in the frigidarium of the Sarno Baths, Pompeii

Yotam Asscher, Ivana Angelini, Michele Secco, Matteo Parisatto, Antonina Chaban, Rita Deiana, Gilberto Artioli

Research output: Contribution to journalArticlepeer-review

Abstract

Multispectral imaging is used to identify and semi-quantify the distribution of pigments in wall paintings based on mineral-specific band ratios. The western wall in the frigidarium of the Sarno baths in Pompeii was imaged using VIS-IR band-pass filters, stacked as multispectral data, and different pigments were measured using portable X-ray fluorescence (pXRF) and fiber optic reflected spectroscopy (FORS) to determine their chemical composition and spectral signature. Cuprorivaite and hematite were found to be the main minerals in blue and red pigments, with higher amounts of copper and iron respectively. Proportional relations were found between cuprorivaite specific band ratios from multispectral and FORS data and the intensity of copper in pXRF spectra, allowing to map the mineral content on a large scale and determine their relative concentrations. These results were confirmed by X-ray powder diffraction (XRD) and thin section analysis on painted fragments that were detached from the wall paintings and found below. This contribute indicates that on-site portable instrumentation could identify specific pigments and determine their 2D distributions based on non-invasive diagnostics of chemical composition and spectral reflectance in wall paintings.

Original languageEnglish
Pages (from-to)317-323
Number of pages7
JournalJournal of Cultural Heritage
Volume40
DOIs
StatePublished - 1 Nov 2019
Externally publishedYes

Bibliographical note

Publisher Copyright:
© 2019 Elsevier Masson SAS

Keywords

  • Fiber-optic reflected spectroscopy (FORS)
  • Multispectral imaging
  • Pompeii
  • Portable X-ray fluorescence (pXRF)
  • Wall paintings

ASJC Scopus subject areas

  • Conservation
  • Chemistry (miscellaneous)
  • Archaeology
  • Materials Science (miscellaneous)
  • General Economics, Econometrics and Finance
  • Spectroscopy
  • Computer Science Applications

Fingerprint

Dive into the research topics of 'Combining multispectral images with X-ray fluorescence to quantify the distribution of pigments in the frigidarium of the Sarno Baths, Pompeii'. Together they form a unique fingerprint.

Cite this