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Figuring out what killed crazy Caravaggio

Caravaggio's The Crucifixion of St Andrew, made in 1607 when the artist was on the run. Credit: Wikimedia Commons

Caravaggio’s The Crucifixion of St Andrew, made in 1607 when the artist was on the run. Credit: Wikimedia Commons

“Caravaggio’s life was even darker than his paintings.”

This is how Italian microbiologist Giuseppe Cornaglia began an account of his uphill battle to figure out what microbial pathogen may have killed the famous and violent 16th and 17th century Italian painter, who died under rather curious circumstances in 1610.

Cornaglia is part of a growing number of researchers who look into the dental pulp of skulls found in graves, in search of DNA from ancient pandemics. The field is called paleomicrobiology, and it’s been used to figure out what microbes caused the Plague of Athens, which indirectly helped Sparta topple Athens in the Peloponnesian War, and which in turn instigated the decline of classical Greece.

Paleomicrobiology has also been used to show that tuberculosis was already in the New World before Columbus showed up carrying a host of other deadly pathogens on board.

So, given that Caravaggio died under strange circumstances (more on that in a second), Cornaglia wanted to look at Caravaggio’s remains and see if he could detect the presence of a deadly pathogen in the artist’s dental pulp. Dental pulp harbors the DNA of microbes present in the person at death. The pulp tissue is covered by protective enamel so that contamination from other microbes can’t occur during the intervening centuries, before forensic researchers dig up the skeleton and crack open the tooth.

The first problem Cornaglia faced was that he didn’t know where Caravaggio’s remains could be found.

This is not entirely surprising when you learn more about the painter.

Caravaggio was an angry guy and quick to pull out his sword. During a fight in 1606, at age 35, he tried to castrate his opponent during a street brawl in Rome, Cornaglia said. The castration was successful. But it also killed Caravaggio’s foe, leaving Caravaggio with a murder charge and a life on the run. Continue reading →

Was antiquity really so tacky?

Many Greek sculptures were painted garish colors. Credit: Stiftung Archäologie, Munich

Many Greek sculptures were painted garish colors. Credit: Stiftung Archäologie, Munich

The ancient Greeks did it, and now the Phoenicians too.

Over the past few years, it’s become increasingly clear that many of the white marble statues from Greece’s golden era were originally painted in garish colors.

The discovery of pigment residues on a multitude of classical era sculpture has been a boon for lovers of kitsch and a downer for pretty much everybody else.

Yeah yeah, I know it’s good to know The Truth, and it is fascinating that they had such bad taste but, well… Sigh.

So it turns out that the Phoenicians, an ancient Semitic seafaring civilization who traveled around the Mediterranean from about 1500 BC to 300 BC, also painted and gilded their carvings.

The Phoenicians invented an alphabet later adopted by the Greeks. One wonders if the Greeks also got their predilection for painting sculptures from the Phoenicians?

This lion's face had traces of iron painted around its mouth, nose and eyebrows, but nowhere else. The iron most likely corresponds to red iron oxide pigments.

This lion’s face had traces of iron painted around its mouth, nose and eyebrows, but nowhere else. The iron most likely corresponds to red iron oxide pigments.

A team of French and German researchers analyzed the surface of several Phoenician ivory sculptures held at the Badisches Landesmuseum Karlsruhe, in Germany, and found metal traces corresponding to ancient pigments and (gold) gilding. These metal traces are invisible to the naked eye, but can be detected using a technique called X-ray fluorescence.

Ina Reich, the lead researcher of the Analytical Chemistry paper reporting the discovery, says she’s also found the same type of metal residues on Phoenician pieces at the Louvre–work which will be published elsewhere in the future. (I wrote a more science-y news article on the discovery here.)

For the lovers of nanoscience out there, here’s a teaser: Reich also mentioned that some of the traces of leftover gold from Phoenician gilding had formed curious gold nanoparticles on the surface of the ivory after spending centuries underground.

Reich is currently analyzing the gold nanoparticles, which she says would be impossible for forgers to emulate and thus may be a new cool new way to authenticate Phoenician ivory.

When a Rembrandt copy is not a forgery

Top: The original. Middle: The mock-up. Bottom: Mock-up & portrait below.  © J. Paul Getty Trust

Top: The original. Middle: The mock-up. Bottom: Mock-up & portrait below. © J. Paul Getty Trust

So you’d think that making a replica of a Rembrandt might be frowned upon by the art world, but this copy of “An old man in military costume” has full approval of its owners.

In fact, the folks at the Paul Getty Museum in LA, asked their own intern to replicate the masterpiece as well as the hidden painting beneath it.

It seems that there’s a pretty good reason for making the copy, or “mock-up” as the researchers call it.

For years, museum researchers have known that there’s another painting beneath the military portrait. But they’ve had a tough time getting more than just a faint whiff of the image hidden below using standard analytical methods.

Over the past few years, a new technique called scanning macro X-ray fluorescence (MA-XRF) has proven itself useful for uncovering hidden paintings on canvases by Van Gogh, Goya and others.

The question is whether MA-XRF would work for Rembrandt’s military portrait. And specifically, whether a portable X-ray device was powerful enough to do the trick or whether the painting should travel to a more a powerful synchrotron X-ray source, such as in Hamburg (DESY) or at Brookhaven National Labs in New York.

It comes down to the fact that museums don’t like shipping valuable and fragile art around the world unless it’s absolutely necessary.

Enter intern Andrea Sartorius (who I momentarily hoped was a descendent of the 17th century Croatian weight-loss fanatic & innovator, Sanctorius Sanctorius. Sadly the names are not quite the same.)

Anyway, Sartorius painted a copy of the original Rembrandt using the same kind of pigments and binder that he would have used, and she included another portrait below the military one.

Then the copy was shipped around the world to be analyzed using X-rays from the various synchrotron sources and from the portable device. Turns out it’s worth the trip to more snazzy X-ray sources if you want to see the hidden painting below. The team argues in this paper that transporting the Rembrandt to a synchrotron facility is actually “useful and relevant.”

The paper’s lead researcher, Matthias Alfred, praised the mock-up: “It is the first time that a painting was reproduced in such an elaborate way for these tests.” It seems that experiments on mock-ups help museum staff decide whether sending expensive art to outside labs for analysis is worth the risk and effort.

And that, my friends, is how a fake Rembrandt can sometimes be a good thing.

Dirty Dishes: Fatty residues on pottery fragments point to 6000 B.C. cheese-making

This pottery sherd was part of an ancient strainer used by prehistoric humans to separate cheese curds from whey. Credit: Nature.

Nearly eight thousand years ago in an area that is now called Poland, a prehistoric person skipped dish-duty.

Thanks to this delinquency, researchers in Poland and the UK led by Richard Evershed have been able to analyze the dirty residues on these dishes.

Today the scientists report in Nature that the fatty acid leftovers are Northern Europe’s earliest evidence for cheese-making.

And tomorrow, teenagers everywhere will begin arguing that dirty dishes buried under beds are a gift to future archeologists.

But seriously, archeologists are interested in the onset of cheese-making for several reasons. Continue reading →

The military borrows from cultural heritage science.

This illuminated manuscript has helped out the US army’s remote sensing. ©Lorenzo Monaco, Praying Prophet, National Gallery of Art, Washington, Rosenwald Collection

Civilian society constantly makes use of aerospace and military inventions:

Can anyone say the Internet? Or transparent braces? (These nearly invisible dental devices are made from a material called polycrystalline alumina, which was initially developed by NASA “to protect the infrared antennae of heat-seeking missile trackers,” notes Discovery.com)

Cultural heritage also borrows from NASA: Portable X-ray fluorescence spectroscopy (XRF) was developed for MARS missions, so that roaming rovers could assess the chemical make-up of rocks on that planet.

Now XRF is a must-have tool for conservation scientists, who want to analyze the chemical composition of art that cannot be transported into a lab, such as a cave painting or Renaissance fresco.

But what about reversing the direction of technology export, so that cultural heritage scientists return the favor by developing new analytical tools for art research that then get delivered to the greater world of science?

This has not happened—until now*. Continue reading →

Weeping Paintings

Otto Piene’s Harvest began to shed white tears in 2000, seven years after it was completed. Credit: ICOM-CC publications.

You don’t really expect a seemingly dry painting to suddenly start oozing streaks of wet paint, seven years after its completion.

So when Otto Piene’s Harvest, which was finished in 1993, began to weep white paint in 2000, owners, conservators and the artist were all rather surprised.

Although Harvest is Piene’s only work to start weeping, the strange liquefying process has happened to dozens of other artworks from contemporary artists as varied as Jonathan Meese and Frank von Hemert, explains Jenny Schulz, a conservator in Cologne, Germany, who’s made it her business to figure out why. “It’s quite a common thing,” she says.

Taking a closer look at several of these paintings, Schulz figured out something that all the weeping paintings had in common: The tears occurred in places on the canvas where the artist has laid down a thick layer of oil paint.

A close-up of the tears from the thick, white base layer on Harvest by Otto Piene. Credit: ICOM-CC publications.

Although the thickly-laid paint seems to dry, it turns out to be unstable and capable of liquefying. But why? It’s not as if applying thick layers of oil paint is a new thing among artists… Yet the weeping painting issue is relatively new, having emerged in the last two decades or so.

What’s changed, Schulz says, is formulation of oil paints. Until recently oil paint was made using linseed oil. But the problem with linseed, she says, is that it has a tendency to yellow over time.

So paint formulators began exchanging linseed oil for sunflower oil, because sunflower oil doesn’t yellow.

The problem is that sunflower oil doesn’t dry as well. That’s because the oil contains fewer reactive double bonds, which are required to form a permanently dried paint complex, Schulz says.

Thick layers of the sunflower oil paint may seem to dry, but they are unstable. Subjected to changes in temperature and humidity or even the jostling that occurs during transport, these layers can collapse, releasing component parts as a gooey tear running as fast as 2 centimeters per month. Continue reading →

Fashion Fights In The 1600s: Parents Just Don’t Understand Their Kids’ Clothing Styles

Flinck’s final portrait of Dirck (left) compared to the more fashionable original (right). Courtesy of van Eikema Hommes

Fashion trends come and go but one thing stays the same: Kids and parents often don’t see eye-to-eye on style.

Even in 17th-century Amsterdam.

A great example of this was recently unearthed by University of Delft researcher, Margriet van Eikema Hommes, when she took a closer look at paintings by the Dutch artist Govert Flinck.

Flinck was a pupil of Rembrandt, but he had more commercial success than his teacher.

Case in point: When Amsterdam’s new town hall was built in the mid 1600s, it featured several Flinck works but only one by Rembrandt, and this lone Rembrandt painting was removed after a year, van Eikema Hommes says.

Flinck’s success was probably due to his strong familial connections to Amsterdam’s wealthy Mennonite community, who became his regular patrons. And therein lies the interesting historical fashion-friction.

It turns out that Amsterdam’s Mennonite community favored solemn, dark outfits. Meanwhile 17th-century cool kids wore colorful tights. (Much as modern-day hipsters opt for brightly colored stockings…)

In fact, some members of the Mennonite congregation would strike out against members who wore less conservative, fashionable clothing—clothing that the Mennonites considered indecent, van Eikema Hommes explains.

Against this cultural backdrop, Flinck was asked to paint a portrait of his young Mennonite nephew Dirck. If you look at the final version of the portrait from 1636, the nephew looks pretty much like a conservative young Mennonite.

But looks can be deceiving. Continue reading →

Come To Culture Lab: Science On Art And Artifacts, A Conference Session This Saturday In Dublin At ESOF

The 2012 ESOF conference in Dublin takes place on the other side of the wonderful Samuel Beckett bridge. Credit: Sarah Everts

I’m looking forward to moderating a session on art and artifact science at the Euroscience Open Forum  (ESOF) conference this Saturday morning from 10:45 am – 12:15 pm in the Liffey B room.

If you’re in Dublin at ESOF, do stop by! Here’s what you’ll be in for… (the shortened version of my pitch to ESOF):

When you mention art or cultural heritage science, most people think about authentication of a priceless masterpiece or identification of a pigment on a Rembrandt or a da Vinci.

But cultural heritage scientists are doing this and much much more: They’re helping to conserve and restore everything from spacesuits to plastic sculptures.

They’re developing tools to study artworks and artifacts without actually touching them, so that you can tell if Picasso produced a particular masterpiece with hoity toity expensive artist paint or industrial wall paint.

They’re getting into the minds of ancient cultures by recreating their recipes for everything from hair dye to incense.

And they’re dealing with what some call the digital art crisis: how do you preserve or conserve art that employs obsolete hardware or software, or art that is stored online in fleeting formats or impermanent platforms.

Here’s who’s speaking at the Culture Lab session: Continue reading →

Did Neanderthals Produce Cave Paintings?

This cave art was made around 37,300 years ago, when both Neanderthals and humans inhabited Europe. Credit Pedro Saura.

It may be time to stop using the word Neanderthal as an insult for people we think lack culture, intelligence and any concept of aesthetics.

Or at least that’s what Spanish Neanderthal expert João Zilhão would argue. He’s just published a paper in Science that identifies Neanderthals as possible artists for three paintings in Spain’s El Castillo and Altamira caves.

The work suggests stereotyping Neanderthals as “dumb” may be incorrect, Zilhão says. “From what we know of Neanderthals, there’s no reason to think they didn’t have the capacity” to be creative artists.

Zilhão and his colleagues used an interesting method (more on that later) to date the cave art to between 35,600 and 40,800 years ago…  a time when both Neanderthals and early humans likely coexisted in Europe. (They also dated some 47 other cave paintings, whose younger ages finger humans as the artists.)

This is not the first time Zilhão has found evidence suggesting Neanderthals in Europe were neither cognitively inferior nor less creative than their Homosapien contemporaries in Africa. Continue reading →

Finding The Culprit For Van Gogh’s Darkening Yellows

Van Gogh's Vase with Sunflowers is getting a pigment check-up this week. Credit: Wikimedia Commons.

The Sunflower still-life series is possibly Vincent van Gogh’s most famous work. Unfortunately the warm yellow hues that make the paintings memorable come from pigments that don’t have a long life-expectancy.

During the 19th century, chrome yellow pigments came in to fashion among painters and then quickly went out again, as artists realized that the vibrant yellow color was unstable and would lose its vibrancy when exposed to light.

For example, Claude Monet and Pierre-Auguste Renoir both steered clear of the chrome yellow pigments. But van Gogh threw caution to the wind and continued to use chrome yellow until his suicide in 1890—a tragic hint, perhaps, of his own instability and imminent breakdown.

This week, conservation scientists at the Van Gogh Museum in Amsterdam have been taking a closer look at chrome yellow pigments in Vase with Sunflower, and a few other paintings, to learn more about the degradation problem.
Continue reading →