Did Rembrandt intentionally incorporate arsenic into his gold paint?

Thank you. Listen to this article using the player above. ✖

Chemists at the Rijksmuseum and the University of Amsterdam (UvA) have for the first time established how Rembrandt applied special arsenic sulfide pigments to create a ‘golden’ paint. Using sophisticated spectroscopic techniques, they were able to map the presence of pararealgar (yellow) and semi-amorphous pararealgar (orange/red) pigments in a striking detail of his famous work The Night Watch. Corroborated by study of related historical sources, they conclude that Rembrandt intentionally combined these particular arsenic sulfide pigments with other pigments to create the golden luster.

The discovery was published recently in research paper in the scientific journal “Heritage Science”, by Fréderique Broers and Nouchka de Keyser, PhD candidates at the UvA’s Van ‘t Hoff Institute for Molecular Sciences and researchers at the Rijksmuseum. They conclude that Rembrandt used the rather unusual combination of pigments to depict the golden threading in the doublet sleeves and embroidered buff coat worn by Lieutenant Willem van Ruytenburch. He is the right of the two central figures at the front of the shooting company tableau, accompanying Captain Frans Banninck Cocq.

Insight into Rembrandt’s Artistic Genius

The research on Rembrandt’s use of arsenic sulfide pigments offers new insight into the artistic genius of the master painter. By deliberately selecting and combining these unconventional pigments, Rembrandt showcased his innovative approach to creating the desired visual effects in his paintings. The intricate techniques revealed in his work highlight the depth of his artistic vision and experimentation with materials.

Unusual Pigments Revealed

The discovery of the arsenic sulfide pigments took place in the large-scale research project Operation Night Watch, which started in 2019 and continues to deliver striking results. A full X-ray fluorescence (MA-XRF) scan of the painting had already revealed the presence of arsenic and sulfur in parts of Van Ruytenburch’s clothing. It led the researchers to assume the presence of the well-known arsenic sulfide pigments orpiment (yellow) and realgar (red). A detailed study of two tiny paint samples taken from the painting showed otherwise. High-tech analysis combining light microscopy with micro-Raman spectroscopy, electron microscopy, and X-ray powder diffraction revealed the presence of the more unusual arsenic sulfide components pararealgar (yellow) and semi-amorphous pararealgar (orange-red).

Deliberate Artistry

The deliberate use of pararealgar and semi-amorphous pararealgar by Rembrandt sheds light on his meticulous approach to creating the golden details in his paintings. By strategically combining these pigments with lead-tin yellow and vermilion, Rembrandt achieved a unique and vibrant golden luster that added depth and richness to his artwork. This deliberate choice of materials showcases the artist’s creativity and technical mastery.

This chemical explanation was supported by a comprehensive review of historical sources reporting on the use of arsenic sulfide pigments. It seems that in seventeenth-century Amsterdam, a broader range of arsenic pigments were available than previously thought. These probably arrived through known trade routes from Germany/Austria and Venice to Amsterdam. This is further supported by the reported use of a very similar mixture of pigments by Willem Kalf (1619–1693), a contemporary of Rembrandt in Amsterdam. The researchers therefore conclude that Rembrandt intentionally used pararealgar and semi-amorphous pararealgar, together with lead-tin yellow and vermilion, to create the special orange-‘golden’ paint.

Reference: De Keyser N, Broers FTH, Vanmeert F, et al. Discovery of pararealgar and semi-amorphous pararealgar in Rembrandt’s The Night Watch: analytical study and historical contextualization. Heritage Sci. 2024;12(1):237. doi: 10.1186/s40494-024-01350-x

This article has been republished from the following materials. Note: material may have been edited for length and content. For further information, please contact the cited source. Our press release publishing policy can be accessed here.