CROWN.

In the course of a two-week campaign to perform Raman investigations in May 2022, we systematically analysed all the gemstones adorning the imperial crown for the first time. This was undertaken in collaboration with the Institute of Mineralogy and Crystallography of the University of Vienna. Until then, all the information we had for the 172 gemstones on circlet, cross and arch were handwritten notes from 1977 recording the optical classification of some of them.

WITec Wissenschaftliche Instrumente und Technologie GmbH, a private company specializing in scientific instruments, provided us with a specially-adapted Raman spectrometer that allowed us to measure both Raman and photo-luminescence spectra. Thanks to many years of experience in determining Raman in gemstones, Professor Dr Lutz Nasdala was able to identify all the stones on the crown directly while performing the measurements.

Today, the Imperial Crown is embellished with a total of 71 sapphires, 50 garnets, 20 emeralds, 13 amethysts, four chalcedonies, three spinels, and eleven differently coloured pieces of glass. Further examinations to identify the stones in more detail are planned within the course of the project. For instance, we aim to classify different types of garnets, determine special inclusion phases, and obtain information on the origins or provenance of individual stones. We will continue to only use non-destructive examination methods such as X-ray fluorescence analysis.

Martina Griesser, 4.9.2022

On the reverse of the Imperial Crown’s central cross, niello was melted into the engravings of Christ on the Cross and the accompanying inscriptions, delineating them more clearly against the gold background. Niello is a black-coloured mixture of sulphur and other metals. Early medieval sources report recipes containing the sulphides of silver, copper and lead as main components in various compositions.

Art historical research has repeatedly linked the central cross’s image of Christ with niello decorations on the reverse of the so-called Imperial Cross (Secular Treasury, Inv. WS XIII 21).  This examination thus aimed to determine whether such a connection could be confirmed with regard to the chemical composition of the respective niello decorations using energy-dispersive X-ray fluorescence analysis (XRF). We used a portable device (PART II) that was developed and built at the KHM in the course of a previous research project ("Portable Art Analyzer - PART", project no. L430-N19, funded by the FWF). It allows focusing on the niello’s very fine lines due to its measuring spot of about 150µm.

The results of this analysis show that the niello masses of the crown’s central cross are composed of silver-, copper- and lead-sulphides as well as possibly a small trace of gold, which could come from the silver. In contrast, the niello on the Imperial Cross consists only of silver- and copper-sulphides. Only traces of lead and gold are detectable here, probably due to material impurities. At least from the perspective of the material sciences, such different formulations do not immediately corroborate a direct workshop connection between the two works.

In the further course of the project, we will continue to evaluate this data, qualifying and contextualising it with literature on the making and composition of niello in the Early and High Middle Ages. Moreover, the close examination of the goldsmith’s technique and tool marks on the crown`s central cross, made possible at an unprecedented level by the use of 3D-digital microscopy, might also provide further insight.

Katharina Uhlir, Teresa Lamers (October 18, 2022)

The inscriptions on the enamel plates of the Imperial Crown have recently attracted increased attention from historians. In connection with certain letter shapes on the enamel plates, they argued that the crown could not have been created before the late 11^th century. As a result, the CHVONRADVS named on the arch is said to have been King Conrad III (r. 1138-1152), who is subsequently also identified as the crown’s commissioner. The suggested dating is very different from that found in art historical scholarship.

Within the framework of this project, all inscriptions on the crown will be examined together with exact technological observations for the first time and the findings discussed in a direct interdisciplinary exchange.

The crown has a total of ten inscriptions. They are fashioned in four different techniques and placed across seven different components of the crown: we find both cloisonné and champlevé enamel on the four plates of the circlet, niello on the back of the central cross and, in a technically unusual form, another inscription is formed by the small threaded pearls on both sides of the arch. We aim to examine epigraphically significant aspects of these inscriptions from all angles, both in terms of their respective characteristics as graphism on the one hand and as text on the other. With regard to the graphic execution, it is not only about the style of the writing (palaeography) and its historical classification, but also about its semantic implications. The latter also concerns the arrangement of the writing and conventions of its relation to pictorial depictions. In the case of the texts, we are focusing on linguistic and orthographic circumstances as well as questions of intertextuality (relationship to other texts).

Because of this, knowledge of relevant written sources and their respective reception history is also of great importance. For instance, the texts of the banderols on the enamel panels have repeatedly been associated with the Imperial coronation liturgy in scholarly literature. Central objectives of the present analysis surrounding the inscriptions are the chronological and geographical classification of the crown and its components, combined with an effort to gain a deeper understanding of its semantic significance.

Clemens M. M. Bayer (November 23, 2022)

What significance might arise from historical representations of the Imperial Crown in the context of the project’s objectives? This is the central question guiding the research into the pictorial sources for this project. So far, the literature has focused primarily on identifying medieval representations of the crown. Often these pictorial sources were used to historically contextualise the shape and individual design elements of the Imperial Crown.

However, none of these images can be established with complete certainty as a representation of the Viennese crown for the period before 1500. This led to exceedingly controversial discussions of these examples in the literature. Even if a compilation of these representations hardly promises new insights for the concrete questions of the project, their systematic documentation is nevertheless planned.

Likely made as a preparatory study for his idealised portrait of Charlemagne, Albrecht Duerer’s famous drawing of the Imperial Crown (after 1510), provides a turning point in the way that the crown’s objecthood and materiality are represented. Taking into account this new approach towards more naturalistic representations in the visual arts in general, we decided to focus our research on images from the period after 1500, recording and evaluating as much material as possible. Since May 2022, around 16,000 entries in national and international image databases have been systematically searched and assessed. Based on these efforts, about 550 entries have so far been created in an internal CROWN database.

A detailed evaluation of these entries is still pending. However, one finding we can already ascertain is that while the Imperial Crown was frequently depicted after Dürer, this was rarely done in such detail that a concrete preservation state of the object could be deduced from the images. Notable exceptions like the engravings by Johann Adam Delsenbach published in 1790, the illustrations from a magnificent work by Franz Bock commissioned by Emperor Franz Joseph I and photographic prints from the early 20^th century in the holdings of the Kunsthistorisches Museum in Vienna, however, indeed promise new results for the questions of the project.

Evelyn Klammer (November 18, 2022)

In addition to the systematic collection of pictorial sources, we also aim to collate written historical accounts of the Imperial Crown. This will form a foundational pillar for an interwoven understanding of the object’s material history and, ideally, allow us to trace its present condition back through time. Written sources from the time the crown was deposited in Nuremberg (1424-1796) have never been systematically sifted and evaluated in relation to the crown’s present appearance and object history. An initial survey reveals that they provide valuable insight into historical repairs and interventions.
In contrast, the collection of written sources from the time before 1400, suggests hardly any new insights in this respect. This material has already been researched and debated many times. Nevertheless, we are preparing a carefully curated catalogue of these sources. Our aim is to provide a solid foundation and comprehensive account for further discussions of the crown’s fates in the Middle Ages.