TEMPLATE DESIGN © 2008

www.PosterPresentations.com

Summary A series of 5 blue and 5 red pigments samples* from the Enkleistra of St. Neophytos, the place of reclusion, in Paphos, Cyprus were analyzed to determine the pigments identity and possible alteration products. Fourier Transform Infrared Spectroscopy (FTIR), Variable Pressure Scanning Electron Microscopy - Energy Dispersive X-ray Spectroscopy (VPSEM-EDS), Polarized Light Microscope (PLM), and Binocular (stereo) Microscope (BM) were used to analyze the samples and due to the limitations of the techniques, only inconclusive assignments can be made on the pigments’ identity.

From elemental analysis it is suspected that the blue pigment is lapis lazuli and that there are two different red pigments which are cinnabar HgS and red lead (Pb3O4). However, without phase analysis of these samples, a positive identification cannot be made. Alteration of red to black and dark blue to light blue were observed for the samples analyzed. A possible alteration of Cinnabar is to meta-cinnabar. Documented alteration products of red lead are to plattnerite [β-PbO2] and anglesite [PbSO4]. Fading of lapis lazuli has been attributed to the breakdown of the Al-O-Si in the literature. However, it was not possible to verify if these are the alteration products with the available tools.

Background

Known Alterations Potentially Applicable S16 Cinnabar (hexangonal) to meta-cinnbar (cubic or amorphous) (Red → black)

SEM-EDS

FTIR

Conclusions

References

Acknowledgements

Pigment Identification Red

Elemental analysis by EDS suggests red pigment to be cinnabar or red lead FTIR for HgS and Pb3 O4 in the region below 500 cm-1 not detectable with the experiment run

Blue Blue pigment is a close match to lapis lazuli or natural Ultramarine

Alterations Red (darkening)

Weathering of cinnabar from red to black is a conversion from hexagonal cinnabar to meta-cinnabar (cubic or amorphous)

Blue (fading) Blue pigment shows grayish spots on the surface that may be due to some sort of alteration of the blue pigment or adsorption of salt from the surrounding over the time

Other important points Plaster layer is identified as calcium carbonate Possible presence of gypsum FTIR showed several organic peaks, which may imply the presence of an organic binding media or a Paraloid B-72 coating

•  Casadio, F., Giangualano, I. & Piqué, F., 2004. Organic materials in wall paintings: the historical and analytical literature. Reviews in conservation, 5, 63–80. •  Clark, R.J.H., 2002. Pigment identification by spectroscopic means: an arts/science interface. Comptes Rendus Chimie, 5(1), 7-20. •  Daniilia, S., Minopoulou, E., Andrikopoulos, K.S. et al., 2008. From Byzantine to post-Byzantine art: the painting technique of St Stephen's wall paintings at Meteora, Greece. Journal of Archaeological Science, 35(9), 2474-2485. •  Daniilia, S., Minopoulou, E., Demosthenous, F.D. et al., 2008. A comparative study of wall paintings at the Cypriot monastery of Christ Antiphonitis: one artist or two? Journal of Archaeological Science, 35(6), 1695-1707. •  Del Federico, E. et al., 2006. Insight into Framework Destruction in Ultramarine Pigments. Inorganic Chemistry, 45(3), 1270-1276. •  Mango, C. & Hawkins, E.J.W., 1966. The Hermitage of St. Neophytos and Its Wall Paintings. Dumbarton Oaks Papers, 20, 119-206. •  Mora, P., Mora, L. & Philippot, P., 1984. Conservation of wall paintings, London. •  Petushkova, J.P. & Lyalikova, N.N., 1986. Microbiological Degradation of Lead-Containing Pigments in Mural Paintings. Studies in Conservation, 31(2), 65-69. •  Stylianou, A. & Stylianou, J., 1970. Monastery of St. Neophytos at Paphos, Paphos: The Monastery. •  (1987) The Conservation of Wall Paintings. IN CATHER, S. (Ed.) Proceedings of a Symposium organized by the Courtauld Institute of Art and the Getty Conservation Institute London. •  (2006) Why Ultramarine Fades to Grey. SEED Magazine. •  AZE, S., VALLET, J.-M., BARONNET, A. & GRAUBY, O. (2006) The fading of red lead pigment in wall paintings: tracking the physico-chemical transformations by means of complementary micro-analysis techniques. European Journal of Mineralogy. •  AZE, S., VALLET, J.-M., POMEY, M., BARONNET, A. & GRAUBY, O. (2007 ) Red lead darkening in wall paintings: natural ageing of experimental wall paintings versus artificial ageing tests. European Journal of Mineralogy, 19, 883-890. •  BURGIO, L. & CLARK, R. J. H. (2001) Library of FT-Raman spectra of pigments, minerals, pigment media and varnishes, and supplement to existing library of Raman spectra of pigments with visible excitation. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 57, 1491-1521. •  DERRICK, M. R., STULIK, D. & LANDRY, J. M. (1999) Infrared Spectroscopy in Conservation Science, Los Angeles, The Getty Conservation Institute •  ISTUDOR, I., DINĂ, A., ROSU, G., SECLĂMAN, D. & NICULESCU, G. (2004) An Alteration Phenomenon of Cinnabar Red Pigment in the Mural Paintings from Sucevita. e-conservation magazine. •  MANGO, C. & HAWKINS, E. J. W. (1966) The Hermitage of St. Neophytos and Its Wall Paintings. Dumbarton Oaks Papers, 20, 119-206. •  MCCORMACK, J. K. (2000) The darkening of cinnabar in sunlight. Mineralium Deposita 35, 796-798. •  SCHMIDT, C. M., WALTON, M. S. & TRENTELMAN, K. (2009) Characterization of Lapis Lazuli Pigments Using a Multitechnique Analytical Approach: Implications for Identification and Geological Provenancing. Analytical Chemistry, 81, 8513-8518.

•  Wall paintings from St.Neophytos Enkleistra •  Originated in late 12th centuries and have been gone

through restoration through the 15th century •  An example of Byzantine wall painting using Fresco

technique or perhaps a combination of Fresco and Secco •  Chemical characterization and possible alteration of red

and blue pigments sampled from various locations in the Enkleistra

•  Investigation of causes and sources of pigment alteration

OPTIONAL LOGO HERE

Map of the Enkleistra of St. Neophytos (from Mango, C. and Hawkins, E. J. W. 1966)

Investigation of Pigment Alteration in the Wall Paintings at the Enkleistra of St. Neophytos, Paphos, Cyprus Steven Brightup, Sara Kiani, Nicole Ledoux, James Ma, Saurabh Sharma

Instructors: Ioanna Kakoulli, Christian Fischer, Vanessa Muros, Sergey Prikhodko, Jenny Hällström

University of California, Los Angeles

Red Pigment S09

Blue Pigment S13

Peak (cm-1)

Identification

1425 CO32-

stretching

1425 CO32-

stretching

870 O-C-O bending

1725 C=O stretch

1140 asymmetric SO4

2- stretching

1025 C-O stretch

1225

1150 - 950

Overlapping stretching bands for Si-O-Si and Si-O-Al found in

ulltramarine

3400 O-H stretching

- Positive ID of gypsum CaSO4 - Positive ID of plaster CaCO3 - Potentially B72 or other organics - Potential lapis lazuli peak

S13: Blue paint sample from Bema S29: Red paint sample from Bema

Limitations and Future work Limitation

•  Context of the samples: the team did not collect the samples •  Lack of phase analysis on the pigments •  Inability to separate layers for analysis. Most analysis was

bulk (except SEM) •  Time available to do a thorough EDS analysis of the samples •  Lack of in-depth background knowledge of pigments and their

alteration: no clear understanding of what is the exact alteration process the paints have undergone

Future work •  Phase analysis using techniques like XRD (X-ray diffraction)

and Raman Spectroscopy •  Micro-FTIR experiments of the individual layers •  EDS analysis of the various embedded layers •  Dispersion PLM analysis of additional pigment samples •  SIMS (Secondary ion mass spectrometry) for surface

alteration of the paints: higher sensitivity than SEM-EDS •  GC-MS (Gas chromatography-mass spectroscopy) for exact

composition of organic materials in the paints

Team would like to thank Dr. Kakoulli for her great advices during the project. Special thanks go to Vanessa Muros for her help with sample preparation and experimental runs. Also the time and effort put by Christian Fischer and Sergey Prikhodko in explaining techniques and running SEM is greatly appreciated. We are also thankful to Jenny Hällström for helping with optical analysis.

S29 red lead to plattnerite [β-PbO2] and anglesite [PbSO4] (Red → black)

S08 lapis lazuli degradation of Al-O-Si network to release S3

- chromophore (Blue → Grey)

S08 Blue Lack of Cu and other heavy metals rule out other pigments like azurite or Egyptian blue. Based on the physical and optical properties of the particles in the PLM dispersion, blue is can be lapis lazuli (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1)

Atomic %

S16 Red Based on presence of Hg the red pigment is most likely cinnabar (HgS)

Atomic %

S29 Red Based on presence of Pb the red pigment is most likely red lead (Pb3O4)

Atomic %

Alteration

Alteration

Alteration

*not all samples represented by images above