Dear eBay, I Love You. Sincerely, Conservation Science

Dear eBay, I love you. Yours Sincerely, Conservation Science I’ve been conducting a rather unconventional poll. It consists of a single question posed to unsuspecting conservation scientists, typically during conference coffee breaks or at the hotel bar thereafter: “Um. So have you ever bought anything on eBay… I mean, for your scientific work?” What’s amazing is that researchers working with cultural heritage objects as diverse as Picasso paintings, plastic sculpture & toys, and digital art have all answered “yes.” Plastics: So that awesome photo of the Barbies in the sample holder? Several of the PVC dolls were purchased by Matija Strlic on eBay for the Heritage Smells! project. He’s part of a team of researchers trying to find a way to diagnose the health of plastic and paper artifacts in museums and archives by sniffing the gases that percolate off the objects. When a plastic (or paper) artifact begins to degrade it produces breakdown gases. But before Strlic can build a hand-held electronic nose that museum staff can then use to assess the health of their collections, his team needs to develop the analytical tool on old, non-valuable plastic objects. And that’s how he started buying Barbies on eBay. Picasso and friends: Between 1900-1950 many contemporary artists (Picasso, Miró, Kandinsky) began experimenting with using the newly invented industrial wall paint called Ripolin for their artwork instead of hoity-toity artist paint. According to Francesca Casadio, this was for a couple of reasons: First: It dried faster than the professional artist paint—a useful feature for procrastinating painters working on deadline. Second: Using industrial paint was a snub to the stodgy art world who wouldn’t dream of using anything but traditional oil paints. Third: Some artists liked the glossy finish of industrial paint. In trying to find a way to identify a painting produced with industrial paint, Casadio needed examples of Ripolin paint from the early 20th century to practice on. And so she turned to eBay… Digital art: Since the advent of computers and other forms of electrical recording technology (such as audio cassettes or video), artists have been using this media to produce artworks. But how do you watch art stored on an old floppy disk, or on a Commodore 64’s hard-drive, or on a now obsolete form of Bulgarian video? You need the hard-ware and you need cables to connect that hard-ware to a compatible screen. Leo Konstantelos told me it’s the esoteric cables that are sometimes the hardest to find. But he’s been successful on—you guessed...

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

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. When van Eikema Hommes started to analyze the portrait with X-rays, she discovered that beneath the painting was another portrait of Dirck (see the black and white image). The original portrait has Dirck in a left-foot-forward, aristocratic posture (compared to Dirck’s more somber pose in the final version), and the original has Dirck wearing substantially less conservative clothing. In particular, Flinck initially painted his nephew in a wider brimmed, fashionable hat, wearing a shirt with a wider, stylish collar and red tights instead of black ones. You can tell the tights were red in two ways, van Eikema Hommes says. First, you can actually see the red paint shimmering through the top layer of the artwork. But more conclusively, using X-ray fluorescence, she detected mercury on the artwork right where the legs were initially painted… and a common red paint of that era was vermillion, a mercury-based paint. So why did Flick paint over the original, fashionable portrait of Dirck? Probably because Flinck, Dirck or both men got cold feet about offending their Mennonite family members—and Flinck’s patrons. In the words of DJ Jazzy Jeff and the Fresh Prince, “Parents just don’t understand.” “There was nothing I could do, I tried to relax I got...

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

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: Matija Strlič is a senior lecturer at the University College London’s Centre for Sustainable Heritage. He’s involved in all sorts of fascinating projects, from the AHRC/EPSRC-funded Heritage Smells!, which is about detecting the chemical makeup of gases emanating off artifacts to figure out degradation taking place inside, to the EU Joint Programming Initiative called ‘Cultural Heritage and Global Change.’ He’s developing technology to visualize damage in art and artifacts before it is visible to the naked eye. Costanza Miliani is a staff researcher at Italy’s CNR Institute for Molecular Science and Technologies. She’s also responsible  for MOLAB Transnational Access, an EU-funded, roving crew of conservation scientists that travel around Europe providing scientific support to museums and galleries around the continent. In the last couple of years, MOLAB has worked on everything from frescoes in Florence’s Santa Croce Basilica, to Van Gogh’s sunflowers in Amsterdam and rare Aztec documents in Liverpool. In her own research, Miliani develops new non-invasive analytical technologies to study dyes, pigments, binders and their breakdown products. Philippe Walter has been a long-time scientist at the Centre for Research and Restoration of the Museums of France, a research facility located underneath the Louvre in Paris. He’s now taken an academic post at the University of Pierre and Marie Curie. Walter has been involved in a potpourri of interesting projects: From researching the Mona Lisa’s complexion using non-invasive, portable technology, to recreating ancient recipes for ancient Egyptian and Grecian cosmetics. Leo...

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Radioactive Artifacts – A Radium Reprise

Two weeks ago I wrote a post about the wide variety of radioactive artifacts found in museums, such as uranium glassware, radioactive minerals, Pierre and Marie Curie lab memorabilia and Manhattan project relics. I decided to give radium-containing artifacts their own post, in part because the radium isotope Ra-226 appears in such a curious variety of items from 1898 through to the 1960s. Pretty much anything that needed to glow in the dark got coated with radium paint during that era. For example, a National Parks Service bulletin warns museum curators to keep an eye out for radium-containing chamber pot lids, light-switches, doorknobs and religious statues. (I searched long and hard, and sadly in vain, for an image of a radium glow-in-the-dark Virgin Mary or Shiva or Jesus.) Of course glow-in-the dark-radium paint is best known for making watch and compass faces as well as cockpit gauges visible at night. (A moment of silence, please, for the 4000 female workers in factories that produced these products in the 1910s and 20s. Repeated licking of the paintbrushes used to apply the radium–in order to keep said brushes pointy–took a serious toll: Many workers suffered serious illnesses ranging from bone disease to cancer.) The radium-226 found in glow-in-the-dark watches and other artifacts has a half-life of 1600 years, decaying by means of an alpha particle.  Radium-226 also eventually turns in to radon-222—not precisely the world’s most loved gas. Given the prevalence of glow-in-the-dark radium-226-containing dials and gauges in aircraft (and spacecraft), I called up Lisa Young, a conservator at the Smithsonian’s National Air and Space Museum (NASM) to find out how she deals with radioactive objects in their collection. Young explained that the government sets limits for the amount of radiation that can emerge from a museum display: 2 milli Roentgen (mR) per hour. “But we aim for under 1 mR/hr at the NASM to err on the safe side,” she added. I needed some context for what 2 mR/hour dose means so I did a back-of-the-envelope calculation: According to the Health Physics Society, people who work with radiation in the US can only be exposed to 5000 mR in a year. This means you’d have to stand in front of a radioactive museum display for at least four months, 24-hours a day to get the same amount of radiation permissible to an X-ray technician at work in a year. Since most people don’t spend more than an hour or two in a museum, this 2 mR/hour dose limit makes for a pretty low risk experience. Of course, museum staff has to monitor radioactive objects in their collection to make sure emissions are within...

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Did Neanderthals Produce Cave Paintings?

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. In 2010, he was first author on a PNAS paper that reported a cache of painted marine shells on the Iberian Peninsula in Spain that were produced by Neanderthals.  These shells were dated to 50,000 years ago, about 10,000 years before early humans showed up in Europe. The shells contain mineral pigment makeup that required some skill and know-how to produce. (The makeup was composed of fool’s gold, aka pyrite, and ground hematite, which can be red and black, all mixed in to a base of the rust-colored mineral, lepidocrocite) Not only did this research show Neanderthals were chemists, but it also suggests they painted themselves and wore jewelry. Of course, it’ll take many more of these discoveries before the entire research community is convinced that Neanderthals weren’t as dumb as we thought. (I’m reminded that history is written by the winners—us humans.) In fact, the other cool part of the current Science paper is that Zilhão and his colleague Alex Pike in Bristol used an uncommon technique to date the cave paintings. This method could be used to accurately determine the age of many more cave paintings, which could help provide additional evidence that Neanderthals were relatively civilized—or not. Since radiocarbon dating is not reliable for determining the age of cave art, the scientists relied on a method that measures the levels of uranium and thorium found in calcite crusts that build up on top of the cave art. (Calcite is the same mineral in stalagmites and stalactites.) Trace amounts of uranium but not thorium are found in the water that deposits the calcite on top of the art. Since uranium...

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Finding The Culprit For Van Gogh’s Darkening Yellows

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. The museum’s staff has recruited a group of traveling conservation scientists from Perugia, Italy, called MOLAB to come help out. (MOLAB has a sophisticated collection of analytical equipment that can study artwork without harming it.) It’s not the first time MOLAB has worked on the chrome yellow issue. Last year, they worked with almost the same team of van Gogh experts to discover why chrome yellow turns from bright yellow to a dingy brown in the presence of sunlight. Here’s why: Chrome yellow pigment is primarily lead chromate (which, incidentally, is the pigment for yellow school buses and was also briefly used to color candy in the 1800s—yikes!). Different yellow hues can be made by mixing in lead chromate oxide and lead chromate sulfate. The darkening of the yellow paint occurs because the chromium in the pigment is reduced from a hexavalent (Cr6+) to a tetravalent (Cr3+) state. The team also reported that sulfur compounds in the paint seem to exacerbate the process. The sulfur is probably present from lead chromate sulfate added to modulate the yellow hue. MOLAB has been back in Amsterdam this week to study more van Gogh paintings, says Costanza Miliani, a lead researcher with MOLAB. The plan is to see if sulfur is indeed a culprit in chrome yellow degradation. Hopefully the team will eventually find a way to thwart and reverse this breakdown so that van Gogh’s vibrant yellows aren’t lost...

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