The “Virgin of the Rocks” is a famous artwork by Leonardo da Vinci. The painting exists in two versions. One of them is displayed in the National Gallery in London. It owes its current radiance to an elaborate restoration in which the latest examination methods including image processing technology were used. An M6 JETSTREAM spatially resolving micro X-ray fluorescence spectrometer from Bruker Nano GmbH Berlin played a decisive role in this. It enabled investigations of the smallest paint particles and delved into the depth of the paint layers. Two USB cameras from IDS Imaging Development Systems GmbH provided the necessary optical information of the sample surface and ensured the exact positioning of the spectrometer over the measuring area.

The “Virgin of the Rocks” is a famous work by Leonardo da Vinci and shows the Virgin Mary with the Christ Child, the boy St. John and the angel Uriel in a rock cave. The painting is one of three panels, all from an elaborate and partially sculpted altarpiece made for the Church of San Francesco Grande in Milan. One of actually two versions is displayed in the National Gallery in London. The painting owes its current radiance to an elaborate restoration in which the latest examination methods including image processing technology were used. An M6 JETSTREAM spatially resolving micro X-ray fluorescence spectrometer from Bruker Nano GmbH Berlin played a decisive role in this. It enabled investigations of the smallest paint particles and delved into the depth of the paint layers. Two USB cameras from IDS Imaging Development Systems GmbH provided the necessary optical information of the sample surface and ensured the exact positioning of the spectrometer over the measuring area.

Even great masterpieces can suffer from aging. Color changes such as yellowing or small amounts of damage cloud the brilliance of the colors and must be repaired from time to time. Extreme caution is required with a picture like the “Virgin of the Rocks”. The restorer must study painting techniques and know exactly the chemical composition pf the colors that were used in order not to destroy the uniqueness of the painting. After several years of research into the feasibility and safety of a possible conservation treatment, da Vinci’s London “Virgin of the Rocks” was finally cleaned and restored. The treatment was carried out primarily for aesthetic reasons since the picture had become increasingly darker and less “recognizable” due to the strong degradation of an oil and mastic varnish applied in 1949.

The analytical examinations of the painting were carried out not only before starting the treatment but also during the cleaning. This allowed valuable information to be gathered on the condition of the surface layers as well as the layer structure and the materials used. The examination of the elemental composition simultaneously provides information about the authenticity of the colors.

For example, great artists may have bought some paints “on the open market”, but mixed the typical colors themselves. Thus the colors used can give an indication of the authenticity of a painting. If, on the other hand, the painter is not known exactly or if several contemporary artists worked on the same painting, the type of brushstrokes and the choice of colors can reveal which part of the picture belongs to whom. Thus the second version of the “Virgin of the Rocks” was probably begun by Leonardo da Vinci and continued by his pupil Ambrogio de Predis. The knowledge about Leonardo da Vinci’s painting practice could be greatly expanded and also documented through the analyses.