Restauration and Conservation of Stained Glass

Normandy is today one of the areas of France that retains the
largest group of ancient stained glass. At the beginning of the
XIXth century, an important number of windows moved to the art
market and Rouen was particularly affected by this phenomenon.
The example of Rouen cathedral is well documented and allow
to follow the journey of a medieval stained glass, from the
windows of the church to the collector. The painted glass was
removed from its original location after a restoration, then stolen
by the glass painter in charge. He transformed an hagiographic
stained glass into a small royal portrait, much more adapted
to the market requirements. Then ready to be selled, this work
went to the parisian market, in the hands of art dealers who
had connections with americans collectors. This communication
will retrace the journey of this stained glass, which became the
property of the famous William Hearst.

The following work consist in the restoration of metal archaeological objects coming from the spanish shipwreck El San Diego, which sank in the Philipines coast in the year 1600. After the discovery and excavation of the pieces done (?) by a french team and the archaeologist Frank Goddio, the objects were taken to differents places: Spain, Philipines, Switzerland and France. A group of this pieces are in Basel, Switzerland in the Atelier of  the conservator Olivier Berger, where I did my graduate internship and restoration proyect in the year 2004.

El presente “Estudio y Plan Director de las vidrieras de la Catedral de Santa María de Vitoria-Gasteiz” constituye un profundo trabajo de investigación sobre las vidrieras de la catedral tal y como las conocemos en la actualidad, así como una herramienta de trabajo de gran utilidad para poder comenzar las futuras actuaciones. Sus principales objetivos son, por un lado, ampliar y profundizar en la información que hasta ahora disponíamos sobre las vidrieras y, por otro lado, proporcionar toda la información necesaria para poder afrontar una intervención global en las mismas, tanto de restauración como de creación de nuevas obras.

The initial focus of this research was on the development of a general workflow for the documentation and monitoring of historical stained glass windows using structured light scanning. Therefore windows from different churches, time periods and with different corrosion and damage phenomena were scanned before and after conservation measures. To evaluate the execution of the restoration measures the data was compared using 3D inspection software to examine the differences in geometry between the two scans. Various problems had to be solved, for example, how to deal with heavily reflective surfaces and the extreme contrast between light and dark surfaces, as seen in the borders between 'Schwarzlot' painting and plain glass. The application of materials for matting the surfaces, such as Cyclododecane spray, was impossible due to the high accuracy of the surface measurement required for 3D inspection. Regarding the contrast differences of the surfaces, the creation of exposure fusions and the use of polarization filters to reduce reflections were tested. In addition to the general problems encountered when recording translucent surfaces, the historical glasses caused additional problems in calculating surface comparisons. For example, the windows have to be moved and turned around several times, both during the conservation process and while scanning, causing deformations of the geometry due to the flexible lead rods allowing a certain degree of movement.

"Abstract – Since almost ten years the Institut Européen d’Archéologie Sous-Marine (IEASM) conducted by Franck
Goddio is carrying out underwater excavations in the bay of Aboukir. The two ancient cities of Canopus and Herakleion
discovered under the floods of the Nile yielded abundant material and especially monumental stone work. A laboratory
on board of our ship allows us to make interventions as soon as the objects are out of the water. The following mechanical,
chemical or electrochemical treatments are made in another laboratory in Alexandria. The materials to be treated
are as diverse as ceramics, various stones, several metals, and organic materials. Meanwhile, the results of this conservation
and restoration work have been presented to the public on the exhibition at Berlin and Paris.
Inhalt – Seit fast zehn Jahren führt das von Franck Goddio geleitete Institut Européen d’Archéologie Sous-Marine
(IEASM) Unterwasser-Ausgrabungen in der Bucht von Abukir durch. Die unter den Fluten des Nils entdeckten Städte
Kanopos und Herakleion haben eine Fülle an Funden und besonders monumentale Steinarbeiten. Ein Bordlaboratorium
ermöglicht erste Maßnahmen, sobald die Gegenstände das Wasser verlassen haben. Die weitere mechanische, chemische
oder elektrochemische Behandlung erfolgt in einem anderen Labor in Alexandria. Die zu bearbeitenden Materialien
sind sehr vielfältig: Keramik, zahlreiche Stein- und Metallarten sowie organische Stoffe. Die Ergebnisse der Konservierungs-
und Restaurierungsarbeit sind inzwischen auf den Ausstellungen in Berlin und Paris vorgeführt worden."

Gotrand Auriane, « De l’esquisse au vitrail : Les processus de création dans l’atelier de Claudius Lavergne », communication à l'occasion du 30e colloque international du Corpus Vitrearum, The concept and fabrication of Stained Glass from the middle age to Art Nouveau, Barcelone, Institut d’Estudis Catalans, juillet 2022.

Chronique

Notre-Dame de Paris. Vitraux. Les douze vitraux modernes à la cathédrale Notre-Dame de Paris en 1935 (Auriane Gotrand), p. 183.

Recension de l'article : Bérénice Vallet,  « Le projet de vitraux pour la cathédrale Notre-Dame de Paris en 1935», Point Riche, no 17, juin 2019, p. 45-50.

During excavations at Cerrocuquillo archaeological site (Villaluenga de la Sagra, Toledo), conservation processes have been a priority. In this article we make some reflections about conservation criteria, its limits and how it helps Archaeological
Science. We explain how useful can be Conservation for the popularization of Archaeology and how archaeological reserves
could be the best option to protect Archaeological Heritage.

In this work, the decision-making process involved in the restoration of the eighteenth century paliotto ligneo (wooden altar frontal) della chiesa del Santissimo Crocifisso all'Albergheria of Palermo is presented. Earlier research concerning mirror restoration was based on only a few case studies and the proposed techniques were not suitable for the artwork here. As a consequence, it was necessary to re-examine theories and protocols of modern restoration to plan an appropriate intervention of the altar frontal. Since in this artwork the role of mirrors is not to give back images, as usual, but rather to create special light effects and play of lights, this work aims to find an approach to the restoration of the altar frontal and its decorations that allows a homogeneous overview of the piece. Thus, the mirrors were not substituted or re-created. Only a visual integration of the damaged ancient mirrors was proposed, with the use of metallic-polymeric films, permitting a completely reversible restoration.

(ITALIANO)
Primo catalogo scientifico del corpus delle vetrate rinascimentali lombarde della regione comasca e valtellinese. Consta di 34 schede firmate e datate (2000), incluse nella "Banca ipermediale delle vetrate italiane" consultabile on line (www.icvbc.cnr.it/bivi/), frutto della collaborazione tra il C.V.M.A. (Corpus Vitrearum Medii Aevi) Italia e il C.N.R. (Consiglio Nazionale delle Ricerche) di Firenze - Istituto per la Conservazione e la Valorizzazione dei Beni Culturali. //

(ENGLISH)
The first scholar catalog of the corpus of Renaissance stained glass windows of the Como and Valtellina region (Lombardy). These are 34 signed and dated entries included in the "Banca ipermediale delle vetrate italiane" (www.icvbc.cnr.it/bivi/). This latter is the result of the collaboration between C.V.M.A (Corpus Vitrearum Medii Aevi) Italy and C.N.R. (Consiglio Nazionale delle Ricerche) Florence - Istituto per la Conservazione e la Valorizzazione dei Beni Culturali. //


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"Princely windows. Donations of stained glass windows as an instrument of devotion, memory and representation (1419-1519).


This article (in Dutch) tries to explain why the Burgundian and Habsburg princes and their wives donated money for the installation of glass stained windows in religious and charity institutions in the Low Countries. The focus is on the windows that were donated between 1419, the year when Philip the Good succeeded his father John the Fearless, and 1519, the year when Maximilian of Austria died. Most of these windows did not survive the meteorological and political storms of the past centuries, except for some churches in Brabant and Hainault. Still, this aspect of Burgundian gift culture can be reconstructed by using the accounts of the receiver general of all finance, the highest financial officer of the prince, who registered the donations. These accounts and those of the receivers in the principalities at a regional and local level constitute the main source for the construction of a list of donated windows (see the ‘bijlage’). Next to these financial documents, some cartoons and drawings (especially those in the manuscripts of Arnoldus Buchelius) have been used.
It would be wrong to look at the donations only from the prince’s perspective; the prince could impossibly know which church needed new windows. Monasteries and churches had to lobby actively for donations to finance the building of new churches or the rebuilding of old ones. It is noteworthy that most of the donations for the installation of glass windows were given during or shortly after the prince had passed by, for example on his inauguration tour. A direct contact with the prince or one of his representatives was an effective method to obtain money, or at least to remind him of his duty to protect the church.
At the same time, a donation of a glass window was a relatively cheap contribution to memorial and devotional practices. It was a particular kind of gift exchange. Whereas the gift was tangible and immediate the counter gift was not: an asymmetric exchange occurs of material goods for spiritual goods. With these gifts the prince tried to establish a reciprocal relationship with the hereafter in obtaining divine compensation through the remission of sins. Still, it seems that the churches and convents were carefully selected. The prince had a preference for popular places of pilgrimage, especially for those churches that boasted miracle images of the virgin Mary, as for example the Sablon in Brussels, the Notre-Dame in Boulogne and the church of Our Lady in ‘s-Gravenzande. He also patronised the mendicant orders; they benefited of almost half of the donations for the convents. Next to the Dominicans who traditionally had access to the prince’s household and his favours, a good many observant communities within the Franciscan order received subsidies. Furthermore, the Burgundian dukes took a special interest in the reform congregations of Sion and Windesheim. This concern was also carried out by duchesses as Isabel of Portugal and Margaret of York who especially favoured the poor Clares. In doing so they joined (or lead?) a more general affection for those convents that were willing to observe the rule of their order more strictly.
Apart from the devotional and memorial aspects the article centres on the political function of the windows. On these ‘bill boards of the Middle Ages’ the princes showed themselves to the public as devote and generous persons. Moreover, by this means they could represent their dynasty, whose members were more and more absent from the Low Countries, continuously to the churchgoers, who were stimulated to pray for the salvation of their souls. This becomes particularly clear in churches with tombs of their predecessors, as for example St. Peters church in Lille, the church of the Carmelites in Brussels and the church of the Black Friars in The Hague. In these churches the prince could visually link his person and family to the reigning dynasty of the past and in this way represent and legitimize his power. So, on the one hand the prince contributed in a material way to the maintenance of the building, and on the other hand he appealed directly to the loyalty of the citizens."

ALUKSI 1920-luku oli suomalaisen kirkollisen lasimaalauksen kultaaikaa. Silloin niitä hankittiin kirkkoihin enemmän kuin yhtenäkään vuosikymmenenä sitä aikaisemmin tai sen jälkeen. Tämän esityksen perustana on pro gradu -tutkielma Kirkollisen lasimaalauksen kulta-aika Suomessa -Suosion taustan tarkastelua. Tutkielman tavoitteena oli kartoittaa niitä syitä, jotka nostivat lasimaalauksen suosituksi kirkkotaiteen muodoksi juuri tuona ajankohtana. Lasimaalauksia on tarkasteltu osana laajaa kontekstia, jossa tärkeimpinä toimijoina olivat taidekenttä ja evankelis-luterilainen kirkko. Lasimaalausten asema muodostui näiden sekä historiallisten, yhteiskunnallisten ja kulttuuristen muutosten leikkauspisteessä mielenkiintoiseksi ja monisäikeiseksi, mutta myös ristiriitaiseksi.

Abril 2021 ARCOVE no se identifica necesariamente con las opiniones y afirmaciones reflejadas en las distintas publicaciones, sean sus autores o autoras miembros o no de la asociación y, por tanto, corre a cargo de estas personas el responsabilizarse del contenido de sus escritos y de las posibles

The multidisciplinary EC VIDRIO project has the purpose of providing a better understanding of the effect of the environment on glass surfaces and paint (grisaille) and to evaluate the efficiency of the protective glazing system, in order to find sustainable solutions to protect ancient stained glass windows from the main causes of glass weathering, in particular the condensation phenomenon. Hence, a new device, named “dew point sensor”, was built and patented to protect the stained glass windows by detecting the condensation on the glass surface. The research was focused on laboratory tests and experimental campaigns: two important French monuments, Sainte-Chapelle in Paris and Saint-Urbain Basilica in Troyes, were monitored, while the study in Cologne Cathedral (Germany) is still in progress. Three different systems were used to detect the phenomenon of condensation in order to evaluate and compare their accuracy and reliability: the indirect measurement through mathematic calculations using air temperature and relative humidity, and two direct measurements by means of the dew point and the leaf wetness sensors. The laboratory tests and research in the field made evident the errors associated with the measurements of the condensation process, and the accuracy and reliability of the new device. The efficiency of the protective glazing system, as regards to the weathering of the stained glass windows, has been confirmed. In fact, the presence of a protective glazing reduces the danger of condensation on the internal side of the ancient window and also the total time of the high relative humidity values of the air in contact with the protected window.