It was so emotional, recalls Ins Imbert Mathieu upon hearing that Notre-Dame de Paris was actively engulfed in flames during the early evening of April 15, 2019. I was at my apartment in Paris when the news broke, and then we all just ran to the cathedralit was definitely very affecting in the moment. She didnt know it at the time, but the then 21-year-old would end up playing an important role in the resurrection of the 861-year-old medieval architectural masterpiece.Notre-Dame Reopening: Inside the Cathedral for the First Time Since the FireSee its transformation in an exclusive clip from 60 MinutesAs it happens, Ins is the granddaughter of Henri Mathieu, who founded the artistic lighting company Mathieu Lustrerie Atelier in 1948 in Marseille, following the end of World War II. In its heyday, the heritage firm was known for designing and producing opulent chandeliers and other lighting fixtures that would eventually hang in the grandest of htels particuliers and luxury boutiques (Cartier, Herms, and Van Cleef & Arpels are all clients).The chandeliers my grandfather was making were mostly sold to the finest shops that were reselling them to private clients. There used to be five or six such shops in any city, and now it may only have oneif that. By the 70s, styles were changing, and the demand for elaborate lighting began to wane. When production was big, he had 100 people working for him, says Mathieu. When he died in 1982, his widow, Yvette Mathieu, inherited the business and reduced its production, which, by this time, consisted of more contemporary lighting lines designed by her husband over the previous decade. She also began taking on more restoration work to keep the companys lights on (pun intended).Two of the 13 chandeliers as they looked while awaiting restorationat Mathieu Lustreries atelier in the village of Gargas in Provence. One of the chandeliers came crashing down during the fire, and two others had stones from the roof fall on them, so these three were quite damaged, recalls Ins Imbert Mathieu.Photography courtesy Mathieu Lustrerie AtelierIn 1992, the couples sonand Inss fatherRgis Mathieu took over and doubled down on the restoration concept while still maintaining the brands artistic arm. He was able to use all the existing machinery to duplicate the models he was restoring and then sell them as reeditions, she explains about the workshop, which is now based in the village of Gargas in Provence. With the permission of the historic monumentslike the Palace of Versailleswe duplicate chandeliers, with their authorization, to an exacting degree, while others might just produce them in the style of. Its these relationships with private and government agencies overseeing historic properties, including Chteau de Fontainebleau, Assemble Nationale, Muse du Louvre, Palais Garnier, and Htel de Crillon, that set the 76-year-old firm on track to help illuminate a darkened Notre-Dame.Three years after the devastation, in July 2022, Ins joined the family business as a project director, following an internship with Maison Lesage in Indiawhere, in part, she managed quality control during Paris Fashion Weekand a two-year tenure with haute couture trimmings factory Declercq Passementiers in Paris. It was during that time that she discovered the art of patience and how to create things by hand, she says. At this same time, there was a lot of conjecture as to whether the damaged lighting from the cathedral would be refurbished or completely replacedor even left out altogether.We passionately waited for the appel doffres (or the call for bids from companies to participate in the Notre-Dame restoration) to come out, she says, noting that the lighting was one of the last elements to be addressed by the tablissement public overseeing the project. The notices came out at different stages during the restoration, and for a very long time we thought maybe all the chandeliers had been destroyed, or that they didnt want chandeliers at all anymore. In a lot of contemporary churches these days, there are no chandeliers. But thankfully, we got word the call was coming.For the lighting restoration, the majority of work revolved around painstakingly cleaning decadesif not a centurysworth of grime.Photography courtesy Mathieu Lustrerie AtelierThe restored chandeliers and candelabras on display at Mathieu Lustreries atelier in Provence before their return to Notre-Dame earlier this fallPhotography courtesy Mathieu Lustrerie AtelierIn September 2022, the notice was announced along with the scope of work required to undertake the restoration. We went on a site visit to where the lighting was being stored just outside of Paris, along with seven other companies competing for the job. Facilitating the damage assessment, application process, and, subsequently, the monumental Notre-Dame restoration project would become her first tasks just two months into the new role. Following the initial inspection to determine the extent of the damage, it took Mathieu three weeks to complete and submit the application, but history was on the companys side. In 2015, her father undertook another restoration job for Notre-Dame: An enormous crown of lights that hung from the center of the cathedral needed some major TLC. Italong with most of the chandeliershadnt really been cleaned or retouched since electricity was introduced, she says, noting that had probably occurred during architect Eugne Viollet-le-Ducs restoration in the 19th century. (Ironically, the crown would be spared from the fire four years later, since the decision was made to install it at the Cathdrale Saint-Denis in a northern suburb of Paris following the refurbishment.)As it turned out, the published bid for work looked familiar. In the offer they give you examples of what they need and how they want the restoration to go, and it was literally a cut and paste of the document we submitted at the end of our project in 2015 that detailed what we did for the crown of lights, Mathieu says. So we felt we were in a very good position! And after a nail-biting five months, Mathieu received word that theyd been selected to undertake the restoration of 64 lighting objects that included 13 chandeliers, four candelabras, and 46 wall sconces, as well as the Sanctuary Lamp signifying the presence of God in the 12th-century cathedral.After an off-site analysis was performed on the metal of the many lighting fixtures, it was determined that they were gold-plated and not gilt. Luckily, matching the original color of gold was made easier thanks to a set of sconces that had been well-kept in an undamaged part of the cathedral.Photography courtesy Mathieu Lustrerie AtelierIn July 2023, Mathieu and five colleagues returned to the storage facility in the outskirts of Paris to retrieve the treasures. Because of all the lead [from the cathedrals roof] and other toxins, we had to clean everything in advance before transporting it to our workshop in Gargas, so they were safe to work on without risk [for our health]. Miraculously, the extent of the damage wasnt overwhelming. One of the chandeliers came crashing down during the fire, and two others had stones from the roof fall on them, so these three were quite damagedmeaning they were heavily scratched and bent, she continues. Fortunately, we were so happy to maintain 90% of the original materials and only had to produce a few new parts to replace what could not be repaired. Apart from thatand the realignment and reshaping of some elementsa lot of the work was cosmetic.That was the big worry, she shares. You always want to keep as much of the original piece as possible without having to recreate it. Instead, the majority of work revolved around painstakingly cleaning decadesif not a centurysworth of grime and tending to the gold plating. At first we werent able to tell whether the pieces were gilt gold or just gold plated. After an off-site analysis was performed on the metal, the verdict was in: We were very disappointed, actually, she laughs. Because gilding is much better quality, we were sure that must be the case, but sadly, it wasnt. Selecting the right color of gold, however, would prove to be a difficult task. With gilt gold theres just one color, but when its a varnish there are many colors, and we didnt have a baseline because the gold plating was very poorly kept. Luckily, in an undamaged part of the cathedral there were some sconces that had been cared for and were in good condition as a color match. It took our doreurs (or gilders) about a week to develop the right color, she explains. We did color tests all times of day and under artificial light, and theyd say, Add one touch of green, now a drop of red, until they got it just right.Eleven months after taking charge of the lighting, Mathieu Lustrerie completed its meticulous restoration efforts this past June when, in partnership with Notre-Dame, it opened its workshop for a three-month public viewing of the now restored fixtures.Photography courtesy Mathieu Lustrerie AtelierEleven months after taking charge of the lighting, Mathieu Lustrerie completed its meticulous restoration efforts this past June when, in partnership with Notre-Dame, it opened its workshop for a three-month public viewing of the renewed fixtures. There were several such exhibitions outside of Paris, and one in the Louvre, inviting people to see the treasures of Notre-Dame that one may never see up close again, Mathieu says of the firms open house that ended with the return of the pieces in early Septemberand subsequent reinstallation in the historic cathedralin advance of its December 8 reopening. People were crying; it was really quite emotional. But of course, were proud of the work weve done, and very happy everything is back where it belongs.