71 research outputs found
An EPR study on ancient and newly synthesised Egyptian blue,
Two sets of ancient roman Egyptian blue (EB) samples and one set of EB samples synthesised in our lab, were analysed by EPR spectroscopy, a technique not commonly used in this field. The spectroscopic parameters obtained were used to attempt the discrimination of the provenance and of the manufacturing techniques of the investigated samples. The results obtained show that EPR technique could be very useful for this purpose.
Furthermore, the similarity of the obtained parameters between the ancient and new samples testify the successful attempt to reproduce the EB according to the chemical knowledg
Aragonite in Roman Wall Paintings of the VIII° Regio, Aemilia, and X° regio, Venetia et Histria
ABSTRACT
In the Roman wall paintings different white colours were used, named Paraetonium, Melinum, Anularia, Eretria, Argentaria, etc. FTIR, Raman spectroscopy and X-Ray diffraction were applied to study different white pigments, such as calcite, aragonite, dolomite and huntite, white carbonates present in archaeological findings from roman walls in the Mediterranean region. This study showed that it is possible to distinguish and identify these components in white colours. About 450 samples of Roman wall paintings were analysed and it was observed that often aragonite is associated to precious coloured pigments. On the basis of the obtained results some considerations about the period in which the different kinds of white pigments were used are proposed
A pilgrim’s ampulla from San Giacomo in Paludo (Venice). Provenance hypothesis through lead isotopic ratio analysis.
Analysis of pigments from Roman wall paintings found in Vicenza
The analysis of about 60 samples of wall paintings was carried out using different chemicophysical techniques: optical microscopy, scanning electron microscopy (SEM) equipped with an EDS microanalysis detector, X-ray powder diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The identified pigments were cinnabar, hematite, red ochre, celadonite, cuprorivaite (Egyptian blue), yellow ochre, goethite and carbon. Only in one case some lead white was found instead. In general, the mortar preparation did not correspond to the complex structure suggested by Vitruvius (De Architectura), but it generally showed a porous layer, with crushed grains under the pigment layer. In certain cases two superposed pigment layers were found: yellow superimposed on both red and pink, black on pink, green on black. (C) 2003 Elsevier B.V. All rights reserved
The Provenance of Sand in Mortars from Roman Villas in Ne Italy: a Chemical-Mineralogical Approach
ANALISI DI FRAMMENTI DI INTONACO DALLA “CASA DELL’ISCRIZIONE DIPINTA” A HIERAPOLIS DI FRIGIA
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