Chemical Characterization of Pope Pius VII Ancient Ecclesiastical Vestment by a Multi-Analytical Approach

Donata Magrini,Susanna Bracci,Barbara Salvadori,Roberta Iannaccone,Lucia Nucci

doi:10.3390/heritage4030090

Abstract

This paper presents a multi-analytical investigation performed for the study of the ecclesiastical vestment, with insignia, of Pope Pius VII, painted from the end of the 18th up to the beginning of the 19th century, made of five clothing elements: chasuble, stole, maniple, chalice veil and purse. The aim of this research was to assess the conservation state of the silk and painted backgrounds; to define the manufacturing technique of the work; to localize, if present, the underdrawing and any retouching; to identify the pigments and, where possible, the binders used. A diagnostic protocol was developed based on preliminary investigations through multiband imaging techniques known as MBI (visible, ultraviolet-induced visible luminescence (UVL), near-infrared reflected (NIR) and infrared reflected false color (IRRFC) photography). The images acquired with MBI techniques ensured a more specific choice of spots to be analyzed directly in situ by non-invasive techniques. In particular, portable digital optical microscopy and X-ray fluorescence (XRF) were performed. Two fragments detached from the chasuble were also analyzed by microFT-IR, microRaman, scanning electron microscopy (SEM-EDS) and gas chromatography/mass spectrometry (GC-MS). Application of the multi-analytical protocol enabled the materials used to be characterized and helped to define the peculiar execution technique used. The presence of an underdrawing made with a carbon pencil was highlighted by MBI. Red lakes, iron-based pigments and copper-based pigments have been identified on the painting palette, applied with arabic gum as a binder.

Highlights

As reported in the literature, literature, multispectral multispectral images images applied applied to to historical historical textiles textiles can can highlight the presence of interesting features, such as the weaving technique highlight the presence of interesting features, such as the weaving technique [24,35,36,37]
The presence of arabinose, rhamnose, glucuronic acid and galactose, as reported in Table 2, indicates the use of an arabic gum in both samples, in agreement with the results obtained with microFT-IR-ATR. The peculiarity of these liturgical vestments lies in the fact that they are painted, and not embroidered with colored threads such as the textiles traditionally made in this period
A preliminary observation performed by imaging techniques, especially near-infrared photography, allowed the presence to be highlighted of an underdrawing made with a carbon pencil and mainly outlined by a very thin line

Summary

Introduction

Several articles describe the characterization of ancient liturgical textiles, their manufacturing process and dyeing techniques [1,2,3,4,5,6,7,8,9,10,11,12,13]. These studies are mainly devoted to the characterization of the materials and are generally performed by micro-invasive analytical techniques [8,9,10,14]. Despite the great interest in this kind of artifact, not many works are based on the application of non-invasive protocols [15,16,17,18,19,20,21]

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Conclusion