Theban Microscopic Analysis

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Raman Microscopic Analysis of a Multi-Pigmented Surface from the Theban Tomb (TT277), Luxor, Egypt
H.H. Marey Mahmoud
Department of Conservation, Faculty of Archaeology, Cairo University, 12613 Giza, Egypt
(Received October 22, 2012; in nal form January 9, 2013)
In this study, the Raman microscopy technique was employed for identifying a multi-pigmented surface from the wall decorations of the Theban tomb (TT277), Luxor, Egypt. The Raman spectra were collected in the near infrared excitation line (785 nm Linefocus) of a diode laser source which enables mapping scan of specic areas in only few minutes. The microstructure and microanalysis of samples were performed by the aid of an environmental scanning electron microscopy coupled with an …show more content…

Traces of anatase were found in the yellow coloured areas which can be a contaminant in natural iron oxide deposits. The ground layer was identied as anhydrite with minor amounts of calcium carbonates detected in some samples. The results showed the capability of the Raman microscopy for direct and fast identication of multi-pigmented surfaces in wall paintings and other decorative objects.
DOI: 10.12693/APhysPolA.123.782
PACS: 82.80.Gk
1. Introduction
The ancient city of Thebes is located on the western bank of the Nile River, about 650 km south of Cairo. The typical (elite) Theban tomb type is the rock-cut tomb that consists of two main parts, the underground burial chamber, most often undecorated and there is the deco- rated chapel accessible for the living [1]. At Thebes, the quality of stone is scarce, and therefore most of the tomb chapels were plastered and painted rather than decorated with reliefs. The Egyptians began serious colour manu- facture from about 4000 BC. They introduced …show more content…

The Raman spectroscopy allows the identication of homogeneous materials on the basis of their molecular vibrational spectra, obtained by excitation with visible laser light. This spectroscopy is based on the Raman ef- fect, which concerns to the molecular structure of the objects under analysis. When a monochromatic light impacts on a material, the light is scattered. Most of the scattered light has the same wavelength as the inci- dent light (the Rayleigh scattering) and a small portion is shifted in wavelength due to molecular vibrations and rotations (the Raman scattering) [8]. With this spectro- scopic technique, it is possible to analyze particles in the micron order and to identify species at molecular level with minimum or no preparation at all. In micro-Raman spectroscopy, the laser beam is focused by means of a microscope objective, employing a backscattering con-
guration; thus, the Raman scattered light is collected within the cone dened by the same objective [9]. Since the discovery of the Raman eect, instrumental improve- ments have continued to give new impulses to the Ra- man spectroscopic research such as are the

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