A research project to establish a Chalcochronology - a novel tool for the dating of paintings on copper 1500-1800

Activity: Talk or presentationLecture and oral contribution


During the 16th and 17th centuries, many of the most important European artists painted on copper-supports, including Rubens, Jan Brueghel I, Rembrandt, Frans Hals, Adam Elsheimer, the Carracci-family, Guercino, Guido Reni, and Claude Lorrain.

The dating of these copper paintings has relied mainly on stylistic analyses and the possible presence of artists’ signatures. Even if on some Flemish paintings, a copper plate maker’s stamp is found on the reverse side, very few of these marks can be identified and dated.

Curators until now have not had any scientific method to assist them in placing a painting on copper in space and time.
For the dating of paintings on wood, the advances of dendrochronology have proven its feasibility, allowing museums to achieve an earliest possible date (terminus post quem).
For paintings on canvas, digital technology has recently employed advanced algorithms to construct a weave-mapping based on X-radiographs. In this way, canvases cut from the same roll may be matched and thereby interrelated in time and space.

The purpose of our proposal is to employ advanced X-ray fluorescence (XRF), a non-destructive analytical technique used to determine the elemental composition of materials, capable of accurate and reproducible detection of trace elements in copper, in order to create a chronology of the metal used by the copper smith before the plate was acquired by the artist. The end-result will be to introduce a new technique, a chalcochronology, vital for the dating of the copper used for paintings.

Recent research has documented that the copper produced by the major early modern mines can be distinguished by comparing the amounts and proportions of impurities. Based on the chemical analysis by XRF of a large number of well provenanced and dated objects, such as copper coins, cannons or church bells, Arie Pappot (Rijksmuseum) has established a detailed view of market availability through time and preferential use of copper from different mines. His overview is invaluable to the current research proposal dealing with the dating of paintings on copper based on the provenance of the copper. Further, as a spin-off, our research will contribute to improve the understanding of historic material processing in general.

The approach has already produced a number of promising results: in one case, a copper-support of a Paul Bril (1554-1626) painting (SK-A-1314) at the Rijksmuseum examined. The painting was considered a later copy after a version at the Kunsthistorisches Museum Wien (KHM 5770), dated 1601. Our XRF-tests resulted in a clear match with a type of copper in use in late 16th century coinage, forcing us to rethink the status of this painting.
Several collections with important holdings of paintings on copper have already expressed their interest in this research: the Statens Museum for Kunst (SMK, Copenhagen), the Rijksmuseum (RMA, Amsterdam), and the Gemäldegallerie Alte Meister, Staatliche Kunstsammlungen Dresden (SKD, Dresden).

By presenting our pitch at the NICAS match day, we hope to arouse wider interest among museums with copper supports in their collections and find more case studies that could direct the first stage of this project.
Period20 May 2019
Held atStichting het Rijksmuseum, Netherlands
Degree of RecognitionInternational