Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mona Lisa’s Secret

11.08.2010
X-ray fluorescence spectroscopy unveils Da Vinci’s astounding sfumato technique

Mona Lisa’s mystical smile still puts viewers under a spell. Leonardo Da Vinci attained the perfection and finesse of his paintings with a technique he himself perfected. This technique is called sfumato (from the Italian for “foggy”).

In this method, several layers of color are applied over each other. The colors meld together and lend the face a mysterious glow. Philippe Walter and his team at the Louvre in Paris have now examined the faces of seven paintings signed by the master with a new non-invasive X-ray fluorescence spectroscopy technique. As the scientists report in the journal Angewandte Chemie, Mona Lisa’s secret lies in many whisper-thin layers of a transparent glaze.

Da Vinci’s technique is fascinating. The gradation of color from light to dark is barely perceptible and looks natural. “Neither brushstroke nor contour is visible: lights and shades are blended in the manner of smoke,” says Walter. The details of how the sfumato technique worked have not been determined before. Walter and his colleagues have now used a non-destructive technique, X-ray fluorescence spectroscopy, to track down the secret. The paintings were irradiated with X-rays. Every chemical element then gives off a characteristic fluorescent light, which allows the element to be quantified.

“Until now, the analysis had remained qualitative, because all the pigment layers were considered simultaneously,” reports Walter. “New technical advances and software have now allowed us to resolve cross-sections of the layers and to quantitatively analyze the composition and thickness of the individual pigment layers.” The seven paintings examined—including the Mona Lisa—span over 40 years of Da Vinci’s work.

In the Mona Lisa, the darker areas arose because a manganese-containing layer was applied more thickly than in the lighter areas. The underlying layers containing lead white are equally thick all over. In a painting dating from about ten years earlier, “Belle Ferronnière”, things are different: Here the shade effects are not the result of a glaze shining through; instead, Da Vinci seems to have used a covering layer of color—dark pigments in a classic oil technique,” says Walter. “The master continuously improved his painting technique. In his later paintings he was then able to produce translucent layers made of films of an organic medium ranging from 30 to only a few micrometers in thickness—an amazing achievement even by today's standards.” The long drying time of the individual layers, lasting weeks and months, explains why Da Vinci worked on the Mona Lisa for over four years, leaving the painting unfinished, according to texts from the Renaissance period.

Author: Philippe Walter, Centre de Recherche et de Restauration des Musées de France, Paris (France), mailto:philippe.walter@culture.gouv.fr

Title: Revealing the sfumato Technique of Leonardo da Vinci by X-Ray Fluorescence Spectroscopy

Angewandte Chemie International Edition 2010, 49, No. 35, 6125–6128, Permalink to the article: http://dx.doi.org/10.1002/anie.201001116

Philippe Walter | Angewandte Chemie
Further information:
http://pressroom.angewandte.org

More articles from Life Sciences:

nachricht Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory

nachricht Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>