Conservation of the Ghent Altarpiece continues to reveal the Virtuosity of the Van Eyck Brothers

The project is now in its third and final phase, focusing on the upper  panels of the interior: the Virgin, the Deity, and John the Baptist, surrounded by music making and singing angels, as well as the panels depicting Adam and Eve. Thanks to the  meticulous conservation work led by the Royal Institute for Cultural Heritage (KIK-IRPA),  the breathtaking virtuosity and profound vision of the artists are brought back to life. 

The seven panels of the upper register transcend the earthly spaces depicted in the rest  of the altarpiece, ascending into the celestial realm. To convey this divine splendour, the  Van Eyck brothers employed unique techniques that appear nowhere else on the other  paintings of the Ghent Altarpiece, such as gold and silver leaf glazed with translucent  colours, and complex applied tin-leaf brocades in relief. Cleaning, conserving, and  restoring these elements, much like the entirety of the altarpiece, requires exceptional  precision and extensive scientific expertise. For this reason, the conservation team  working on this masterpiece collaborates with international Van Eyck specialists and  scientists with expertise in each of the various materials. 

As with the first two phases of the conservation-restoration project (the exterior from 2012  to 2016 and the lower register of the interior from 2016 to 2019), the KIK-IRPA team has  encountered extensive overpainting from the 16th century. Scientific research revealed  that these layers were applied over older damage, earlier restorations, and accumulated  dirt and varnish. This shows that the Ghent Altarpiece underwent multiple rounds of  restoration and varnishing before being significantly overpainted in the first half of the  16th century. At that time, painters-“restorers” didn’t merely cover minor damages but  repainted large portions of the panels. 

Chemical analysis of these overpaints uncovered materials characteristic of 16th-century  artworks but unknown in the Flemish art of Jan and Hubert van Eyck’s era. These include  the green pigment posnjakite and ground sodium-rich glass, presumably added to  accelerate the drying of the paint. Such glass was only introduced in the Southern  Netherlands in the 16th century. It was produced in Antwerp at the time and closely  resembled the Venetian original, earning it the name “façon de Venise”. 

Tests confirmed that the non-original layers can be safely removed using the same  methodologies as in phases 1 and 2 of the project, without risking damage to the original  Eyckian paint surface. These scientific procedures have again been endorsed by the  International Commission of Experts (art historians, chemists and conservators with an  expertise in the art of Van Eyck and the 15th century that have been following the project  since 2012), paving the way for the careful removal of the thick, pasty and often heavily  darkened oldest overpaint. This labour-intensive process is gradually revealing the subtle  nuances characteristic of the Van Eycks' mastery.

The cloaks of John the Baptist, the Virgin Mary, and the Deity were most heavily affected  by 16th-century overpainting. Roughly half of these additions have now been removed  from the surface, restoring the vibrancy of the original colours and bringing these central  figures into harmony again with the rest of the altarpiece. The panels depicting Adam and  Eve, mainly covered with layers of varnish and blotchy retouches, have been found to be  remarkably well-preserved in their original state. Following cleaning, they now display the  unparalleled pictorial mastery of the Van Eyck brothers in full brilliance. Cleaning of the  two panels featuring angels is also well underway. 

On November 4, the International Commission of Experts convened at the conservation  studio in the MSK Ghent. The group emphasized the importance of removing the 16th century overpainting to restore the original glory and radiance of the Van Eycks’ work.  The commission praised the team of KIK-IRPA scientists and conservators for their  unmatched expertise, which has been honed over years of dedicated work on this  masterpiece. 

Thanks to this meticulous approach, experts and the public can finally witness the original  Ghent Altarpiece for the first time in centuries. Old damages in the original paint layers  will eventually be retouched using reversible materials, and the seven panels will receive  a new varnish layer at the end of the treatment. Visitors can experience this unique  conservation process firsthand at the open studio at the MSK Ghent, where the team will  continue their work throughout 2025 and 2026.