2013 Paris

My first instinct for the new stained-glass windows in Bayeux Cathedral was to use glass prisms. I wanted prisms that would refract the light in multicolored projections throughout the interior of the cathedral, while retaining the intensity of light that penetrated each window into the very heart of the cathedral.

2013 Bayeux

The colors for each bay window were chosen according to its geographic orientation: the northside windows are composed of a cooler range of lights, and warmer on the southside. Windows facing east, which are lit up in the morning, are clearer than those to the west, where the sun sets.

2013 Bayeux

The prisms are actually faceted crystals made of dichroic glass in the shape of triangles or trapezoids, each corresponding to the shape of the window tracery under each tympanum, whether polylobes. Depending on the angle of view and the exterior light, this type of glass can reflect a transmitted light into different colors inside as well as outside the cathedral.

2014 Munich

The colors chosen for the bay windows, the type of glass in which the crystals were inserted, and the technical problems in mounting them were designed during many visits of close collaboration with the glass workshop of Franz Mayer & Co, in Munich.

2014 Palaiseau

The crystals were conceived and designed with the Institute d’Optique Graduate School, Paris-Saclay. Each one took into account the characteristics and placement of each window, its height, and orientation to the sunlight.

2014 Munich

Along with the optical properties of each crystal, the shape and volume of each was calculated to produce a burst of color on a scale with the grandeur of the cathedral’s windows.

2014 Bayeux

Tests made inside the cathedral helped to refine the tech­nical and aesthetic decisions. It was important to verify, on site, how the crystals and the colored glass would react to the particular light entering the cathedral.

2014 Bayeux

By using lead tracing, the crystal prisms were set in hand-blown antique glass. Each was installed at the crossing of two implied lines, one vertical and one horizontal, but situated at different places in each bay window, in an almost musical composition.

2014 Bayeux

A test window was installed in October 2014 by the Franz Mayer & Co glassworks. This made it possible to specify the characteristics necessary for the antique hand-blown glass in which the crystals would be set along with the mounting techniques necessary for each.

2014 Bayeux

The shape and the techniques necessary for inserting each crystal prism led to the general design of each window. The clear parts, made of antique blown glass, determined the transparency and created a link between the upper and lower parts of each bay window.

2018 Saint-Just

The antique glass panes in which the crystal prisms were set were hand-blown at the Saint-Just glassworks in the Loire Valley. Each plate was made to visibly reveal its hand-manu­facture, which contrasts with the industrially made crystal prisms.

2018 Saint-Just

First, manually blown glass is made and split vertically, then flattened in the oven to form the panes that will surround the prisms, which are then manually set into the lower parts of the stained glass windows.

2018 Cellette

The prisms were cut one by one by Ludovic Sauvètre from a single block of optical glass.

2019 Bayeux

In 2019, work began on bays 120 and 122, which face southwest. It took several months on site for the stone masons to cut and stack the window stones.

2019 Le Mans

In Le Mans, the different elements of the two bays were prepared. There, in collaboration with the Vitrail France glassworks, the technical constraints of the stained glass were worked out and assembled in accordance with the spirit of the project.

2019 Le Mans

The upper parts of windows 120 and 122 are made up of more than 170 pieces of colored dichroic and antique hand-blown glass.

2019 Le Mans

Dichroic glass is made by fusing a glass surface with different metals (aluminum, chrome, magnesium, silicon, titanium, or zirconium), which creates varieties of reflective colors, depending on the angle of view. The method was developed by NASA for satellites to withstand high temperatures. Each piece of dichroic glass was also assembled and reinforced at Vitrail France glassworks.

2019 Bayeux

The technical aspect and quality of dichroic glass allows it to interact with daylight, while also extending the color effects normally seen only at night.

2020 Bayeux

The colors and the effects of the crystal prism change with the weather and with the light, depending on where they are seen from. Visitors at the Bayeux cathedral might also benefit from the nuances typical of the Normandy sky.

2020 Bayeux

Of the eight bay windows on both sides of the transept, two were installed in 2019. The large, nineteenth bay at the south end will be completely restored in 2020. One year’s work is required for the stonework and the glass for each side. The finished work is expected to take until 2024.

2020 Bayeux

In 2014, the art historian Michel Gauthier wrote an essay about the project, entitled, Shards in Stained-glass. It is available here.

2021 Bayeux

In 2021, construction of the masonry and installation of the stained-glass began on the southeast side. During the day, splashes of colors would be reflected onto the white tarp that covered the scaffolding.

2022 Bayeux

In the beginning of 2022, when the two Southeast bays were exposed, the color from the new stained glass windows could be seen from the intersection outside the cathedral.

2022 Bayeux

Throughout the day, the four facing southwest and southeast bays reflect colors and the interior walls come alive in a radiantly colored dialogue between them.