Category → pigments
This blog devotes a lot of digital real-estate to cool experiments on art and artifacts that are non-invasive, or at least minimally so.
So I’ve got to admit that I was not particularly overwhelmed by the breathless reports last week in a myriad of media about a project to drill 14 holes into a Vasari painting in order to search for a possibly hidden da Vinci below.
The articles were subsequent to a press release by National Geographic on March 12, which was presumably trying to raise interest in a documentary about the project airing a few days later (March 18).
Yesterday the well-respected Art-Info published an interesting take-down of the drilling project, entitled “The Search for the Lost Da Vinci Fresco: Serious Science or Irresponsible Hype?”
The piece pointed to a protest-petition against the project signed by 530 members of the museum community, including high-profile curators at the Met and the Louvre.
According to the Art-Info article, none of these critical folks got face-time in the National Geographic Channel documentary. This is how the writer Kate Deimling put it:
- “”Finding the Lost Da Vinci,” which aired on the National Geographic Channel on March 18, certainly looked like an infomercial for the project. The program’s narrator describes opposition to the drilling as a “media feeding frenzy” and an “attack from the press,” but none of the experts opposed to it is interviewed or even mentioned by name. Instead, scientists in lab coats decry the opposition to their work and are then seen boring holes into the painting while dramatic music plays.”
The Art-Info piece also voices criticism from the conservation science community, namely that the pigments detected by the drilling project might be from brick instead of paint.
Another criticism is that non-invasive analytical equipment (such as newer radar technologies) should be used instead of destructive drilling.
In 1521, the Aztec capital of Tenochtitlan fell to the Spanish invaders, who burned libraries and destroyed most of the manuscripts pertaining to Aztec history, religious rituals and economy.
The Codex Fejérváry-Mayer is one of just two dozen or so Aztec texts to survive the Spanish invasion.
It’s also just one of just six screenfold books that were penned before Cortez started his conquest of Mexico’s indigenous people.
So suffice to say that it’s a pretty exceptional record of the pre-Spanish Mesoamerican world.
This codex is called a screenfold book because Aztec scholars would literally twist and fold the 22-page, double-sided document to cross-reference a particular date to two calendar cycles: the yearly cycle of 365 days and the sacred cycle of 260 days (called tonalpohualli).
Joanna Ostapkowicz, a curator at the World Museum in Liverpool, which hosts Codex Fejérváry-Mayer, explains it in this way:
“In the hands of ritual practitioners and other high-ranking individuals, the codex became a guide for people’s actions. The screenfold’s internal reading structure is right to left and is determined by the number-and-sign sets of the calendar: how the images and symbols cross-referenced each other was then interpreted by the reader, who was well versed in the significance of the various icons. Although an object of great respect, the codex was also a tactile, malleable reference tool: a user could consult both sides simultaneously by folding parts of the codex onto itself. Reading it offered guidance on appropriate days to travel, to celebrate a deity’s beneficence with sacrifices, to plant crops or to name a child.”
Many art historians have eyed Three Maries At The Tomb and agreed that it’s a Van Eyck. What’s debated is whether Jan painted the artwork or whether it was his older brother Hubert. Or more likely, whether the painting was a sibling collaboration.
For example, the brothers both worked on the famous Ghent Altarpiece: An inscription on the back says it was started by Hubert and finished by Jan, six years after Hubert’s death.
However, art historians debate which brother had a greater influence on the paintings in the Ghent Altarpiece. Did Jan humbly follow his older brother’s stylistic lead or did Jan turn the artwork into a masterpiece with his own artistic flair? Continue reading →
Consider this cultural cocktail: the 1960s and 70s surfing scene in Los Angeles, that era’s emerging aeronautical and chemical industries, plus a splash of flavor from Hollywood and the Beatniks.
The result is a group of artists called the Finish Fetish who produced minimalist sculptures often made from materials newly available in those decades, such as polyester.
Finish Fetish is “extra spit and polish in pop and minimal art plus space age materials.” This description (from Peter Plagens via artdesigncafe) explains the obsession with “finish”…which should not be confused with the Northern European Finnish.
One of the Finish Fetish is an artist called De Wain Valentine. Commercial resin available at the time “wouldn’t allow him to do what he wanted to do–which was to pour really big objects,” says Tom Learner, head of Modern and Contemporary Art Research at the Getty Conservation Institute.
Valentine wanted to create his extremely large sculptures in a single pour of polyester resin because creating the artwork in two steps interfered with the seamless look he was after. Continue reading →
For nearly 800 years, the Islamic Moors occupied Spain, building extraordinary buildings that still draw hordes of tourists today. Case in point: the Alhambra.
Less well known is the Madrasah Yusufiyya of Granada, the only Islamic university from the Moorish era left standing in Spain. It was built in 1349 and operated for about 150 years, until the Christians conquered the region in the late 1400s.
The lovely Madrasah Yusufiyya was then used extensively by the Christians, most likely as administration buildings, says Carolina Cardell a conservation scientist at the University of Granada.
In fact the Christians liked the building so much, Cardell says, that in the last 500 years they have done a lot of touching up, repainting, restoring and embellishing of paintings covering the stucco and wooden interior walls of the Madrasah Yusufiyya.
Yet art historians haven’t really known the extent of these interventions. So over the past few years, while the Madrasah Yusufiyya has been under restoration, Cardell and her team of scientists took a closer look at the paintings with a suite of analytical technology. She’s just published a paper in Analytical Chemistry about the interventions to the Madrasah Yusufiyya over the past 500 years. Continue reading →
When acrylic paint was introduced in the late 1940s it was a boon for artists with a penchant for instant gratification: Acrylics dry within hours, compared to the weeks and sometimes months it takes for oil paint to completely harden.
But few things in life are perfect, and acrylic paint is no exception. In order to keep pigments stable in the acrylic polymer base, paint makers had to include additives called surfactants. Unfortunately, after a few years or decades, the surfactants get itchy feet and rise out of the paint to the surface of the artwork.
Once there, these surfactants can leave a white film on priceless paintings and they can also be sticky, attracting dirt and grime to the artwork.
In this week’s C&EN, my colleague Celia Arnaud digs deep in to acrylic paint chemistry and talks with conservation scientists about what they do to remedy the problem of wandering surfactant.
Unfortunately, many existing solvents that might be used to clean off the surface of acrylic artworks tend to make the paint swell… This makes museum staff nervous because it’s not clear what long term consequence come from this swelling. Another problem is that solvents that don’t cause acrylic paints to swell aren’t typically good cleaners.
That’s why researchers at the Tate Galleries in London, the Getty Conservation Institute in LA and the DOW chemical company have teamed up to try and find a solvent that cleans but does not swell acrylic paint. At the same time researchers at the University of Delaware are working with Golden Artist Colors, a paint company, to work out good cleaning conditions for acrylic paintings.
If these researchers hit paydirt, acrylic paintings around the world will finally get that facial treatment they’ve all been needing.
When early humans wanted to paint their bodies, cave walls and anything else for that matter, they used ochre, the red and yellow pigments found in earth and rock.
Today archeologists are reporting the discovery of a 100,000 year-old ochre-making workshop—the oldest to date–in the Blombos cave along the Cape coast of South Africa.
This pushes back the date–by nearly a factor of two—for when early humans produced and stored chemical products such as paint. The next oldest evidence of a workshop dates from 60,000 years ago.
The discovery shows that 100,000-year-old humans “had an elementary knowledge of chemistry and the ability for long-term planning,” note the authors of the Science paper (DOI: 10.1126/science.1211535), which includes Norway’s Christopher Hensilwood.
It’s pretty of amazing to think that a group of Middle Stone Age humans had a paint factory in operation.
Apparently the ancient workers first ground the ochre pigments (which are iron oxides and hydroxides) out of rock. Then they heated up animal bones to extract fat and marrow which was used as a binder for the ochre pigments. The early humans also added a bit of charcoal to the mix.
Then the paint was stored in abalone shells. Normally there’s a little air hole found in such shells but the ancient workers blocked the hole so that the paint would last longer. Pretty smart for a caveman (or cavewoman).
Incidentally, up on the embargoed Science media site, where journalists can download photos of the pigment-making artifacts, there’s also sequence of amazing shots of the coastal workshop cave.
I think it’s pretty clear that this workshop discovery also reveals that ancient humans were early adopters of the real estate truism: location, location, location.
Guest post from Carmen Drahl, a C&EN’s Associate Editor and Haystack blogger.
Growing up, I spent every summer in northern Spain, living in my grandmother’s Oviedo flat and wandering the city and surrounding villages with distant cousins. One of my greatest regrets is never having taken the 3 hour drive to what my grandma called “las Cuevas de Altamira”, the storied caves and UNESCO World Heritage Site that house some of the world’s most striking examples of Paleolithic art.
The caves have been closed to visitors on and off since their discovery in the late 1870s. But they’ve been shuttered indefinitely since 2002, because microbial colonies encroached on the priceless scenes of bison and deer on the stone ceilings. Government officials in Cantabria, the Spanish autonomous community where the cave is situated, would like to reopen Altamira to tourists. Today, in a policy forum in the journal Science (DOI:10.1126/science.1206788), researchers led by Cesareo Saiz-Jimenez from the Spanish Council for Scientific Research (CSIC), argue that would be a bad idea. The team, which has been dealing with the microscopic invaders firsthand, says that letting visitors back into the cave’s fragile ecosystem would quickly undo any good that the closure has done and could cause irreparable damage. Continue reading →
In honor of today’s Nobel Prize in chemistry to Dan Shechtman for the discovery of quasicrystals, I thought I’d write a little post on the world of mosaic art conservation.
Bear with me–there is a connection.
(This is precisely what I said when Paula Artal-Isbrand, a mosaics conservator at the Worcester Art Museum, answered the phone. Luckily, she didn’t deem me a random freak and then hang up.)
OK. So back to the Nobel Prize. Quasicrystals are regular patterns of atoms that never repeat themselves, much “like the fascinating mosaics of the Arabic world,” noted the prize’s press release.
This got me thinking–and blogger David Bradley too—because moments later he tweeted the perfect Moorish mosaic example you see here. And I knew I had to learn a bit more about mosaic art conservation and restoration.
Continue reading →