Egyptian Blue's Amazing Qualities

Okay, this will sound totally nutzoid, but this article got me to wondering whether the "alternative history" folks may be right about some aspects of ancient Egyptian technology???  It's only recently that we actually finally deciphered out of what Egyptian blue pigment was made.   I've been posting articles about Egyptian blue and similarly-colored pigments used by other ancient civilizations.  Did the Egyptians know about the qualities of this pigment, and did they somehow use the pigment as other than as a decorative device in ways we are only now discovering for ourselves...  

Tomb of Nebumun demonstrates shades of Egyptian blue pigment.  Interestingly, or perhaps
to be expected, these shades of blue are very popular today in home decor.  Turquoise,
aqua, teal, sky blue, and robin's egg blue, are all featured in today's upscale decor.

From archaeology.org

From Egyptian Blue to Infrared

By NIKHIL SWAMINATHAN

Monday, April 08, 2013

 

Egyptian blue is known as the world’s oldest artificial pigment, first used more than 4,500 years ago, found on wall paintings at Luxor and sculptures recovered from the Parthenon. The hue comes from a compound called calcium copper tetrasilicate. Over the past decade, museum conservators and archaeologists have taken advantage of its properties to spot the presence of Egyptian blue on antiquities: When red light is shone on the pigment, it reflects infrared light, which can be detected via night-vision goggles or cameras.

Chemists at the University of Georgia (UGA) have now determined that the luminescent quality of calcium copper tetrasilicate is retained even when the compound is reduced to what are termed “nanosheets,” a thousand times thinner than a human hair. “Even if you have a single layer, the thinnest possible, you still get the effect,” explains UGA’s Tina Salguero. At that scale, she believes, you can start thinking about modern applications.

Salguero says that Egyptian blue’s primary molecule could be incorporated into a dye to improve medical imaging, since the infrared radiation it would reflect can pass through human tissue. The pigment’s luminescent quality could also be effective for developing new types of security ink, typically used to secure currencies and other official documents from forgery. Further, the possibilities for a second act for the long-out-of-use coloring extend to devices such as light-emitting diodes and optical fibers, both of which transmit signals using the relatively long wavelength of infrared light.

The UGA team is now looking at another compound, barium copper tetrasilicate, which was also used as an ancient pigment, in this case by the Chinese.

Prior posts on Egyptian blue:

Wednesday, May 5, 2010

Ancient "Blue" Back in the News

Prior post - did the old world and new world "blue" hues have something in common? Use the Goddesschess blog search feature, type in the word "blue" (without the quotes), and a whole bunch of interesting articles will appear to give you background on this fascinating, ancient color.

In the news today - ta da! "Egyptian Blue Found in Romanasque Altarpiece"

 

 

Sunday, May 23, 2010

The Color Blue Back in the News

First, a follow-up article of sorts, on the use of ancient Egyptian blue in a 12th century CE altarpiece in a Barcelona church:

Egyptian Blue Found in Romanesque Altarpiece

 

 

Saturday, March 20, 2010

Is There a Common Link Between These Ancient Blue Hues?

I've no idea. I'm not suggesting that the recipe for either blue travelled from Old World to New World or vice versa. I'm wondering is there an underlying chemical conection or similarity in the composition of the minerals in the clay and/or rocks that the Maya used to produce their cobalt blue color and the minerals in the rocks the ancient Egytians used to produce their cobalt blue color?

Mar 16, 2010
Archaeologists: Maya Blue pigment recipe moved around
An archaeologist reports the ingredients of "Maya Blue" pigment beloved by Central America's ancients may have been widely mined, not traded as previously suggested.

 

Tuesday, February 26, 2013

The Latest on Egyptian Blue

Ancient "Egyptian blue" pigment points to new telecommunications, security ink technology
February 20, 2013

A bright blue pigment used 5,000 years ago is giving modern scientists clues toward the development of new nanomaterials with potential uses in state-of-the-art medical imaging devices, remote controls for televisions, security inks and other technology. That's the conclusion of an article on the pigment, Egyptian blue, in the Journal of the American Chemical Society.

Friday, July 30, 2010

Maya Blue Back in the News

From Fox News
X-Rays Reveal Secret of Ancient Mayan Dye
By Devin Powell
Published July 27, 2010

WASHINGTON -- Physicists have created a dye that promises to last for a thousand years. The secret to this extraordinary durability? Its formula is based on a Mayan pigment, a brilliant blue color that survives to this day on the walls of their ancient temples.

Discovery of Formula for Maya Blue Claimed

Story from Live Science

Maya Blue Paint Recipe Deciphered

Megan Gannon, News Editor

Date: 02 April 2013 Time: 05:42 PM ET



A Maya king, seated and wearing an elaborate head dress

of blue feathers, adorns the north wall of the ruined

house discovered at the Maya site of Xultún. An attendant,

 at right, leans out from behind the king’s head dress.

The painting by artist Heather Hurst recreates

 the design and colors of the original Maya artwork at the site.
CREDIT: Heather Hurst, copyright National Geographic Society

The ancient Maya used a vivid, remarkably durable blue paint to cover their palace walls, codices, pottery and maybe even the bodies of human sacrifices who were thrown to their deaths down sacred wells. Now a group of chemists claim to have cracked the recipe of Maya Blue.

Scientists have long known the two chief ingredients of the intense blue pigment: indigo, a plant dye that's used today to color denim; and palygorskite, a type of clay. But how the Maya cooked up the unfading paint remained a mystery. Now Spanish researchers report that they found traces of another pigment in Maya Blue, which they say gives clues about how the color was made.

"We detected a second pigment in the samples, dehydroindigo, which must have formed through oxidation of the indigo when it underwent exposure to the heat that is required to prepare Maya Blue," Antonio Doménech, a researcher from the University of Valencia, said in a statement.

"Indigo is blue and dehydroindigo is yellow, therefore the presence of both pigments in variable proportions would justify the more or less greenish tone of Maya Blue," Doménech explained. "It is possible that the Maya knew how to obtain the desired hue by varying the preparation temperature, for example heating the mixture for more or less time or adding more of less wood to the fire." [Note the different shades of blue to blue-green in the modern reproduction painting.]

American researchers in 2008 claimed that copal resin, which was used for incense, may have been the third secret ingredient for Maya Blue. Their research was based on a study of a bowl that had traces of the pigment and was used to burn incense. But Doménech's team didn't buy those findings.

"The bowl contained Maya Blue mixed with copal incense, so the simplified conclusion was that it was only prepared by warming incense," Doménech said in a statement.

The Spanish researchers say they are now investigating the chemical bonds that bind the paint's organic component (indigo) to the inorganic component (clay), which is key to Maya Blue's resilience.

Among the more remarkable discoveries of the paint in context was a 14-foot thick (4 meters) layer of blue mud at the bottom of a naturally formed sinkhole, called the Sacred Cenote, at the famous Pre-Columbian Maya site Chichén Itzá in the Yucatán Peninsula of Mexico. When the Sacred Cenote was first dredged in 1904, it puzzled researchers, but some scientists now believe it was probably left over from blue-coated human sacrifices thrown into the well as part of a Maya ritual.

The research was detailed this year in the journal Microporous and Mesoporous Materials.

Maya Blue Back in the News

From Fox News
X-Rays Reveal Secret of Ancient Mayan Dye
By Devin Powell
Published July 27, 2010

WASHINGTON -- Physicists have created a dye that promises to last for a thousand years. The secret to this extraordinary durability? Its formula is based on a Mayan pigment, a brilliant blue color that survives to this day on the walls of their ancient temples. (Image Wikipedia)

"This pigment has been stable for centuries in the hostile conditions of the jungle," said Eric Dooryhee at the Brookhaven National Laboratory in Upton, N.Y. "We're trying to mimic it to make new materials."

Dooryhee and team of French physicists have spent years studying historical objects using X-rays. They shoot finely-tuned beams of X-rays from a synchrotron machine -- much stronger than a dental X-ray -- at these materials and look at the pattern of scattered X-rays coming out in order to determine the structure of the atoms inside.

The scientists have used this technology to examine Egyptian cosmetics, Roman pottery, and Renaissance paintings. They have recreated some of these ancient materials and are just beginning to learn how to borrow their strengths to make new modern "archeomimetic" materials that can stand the test of time.

Unlike most organic pigments, which tend to break down over time, the pigment Maya Blue is remarkably resistant -- not only to natural weathering, heat, and light, but also to strong acids and solvents in the laboratory.

Pre-Columbian Mesoamericans, who lived in Central America before the first Spaniards arrived, developed the pigment about 1700 years ago. Archaeologists rediscovered it in 1931 at the site of the ancient Mayan capitol Chichen Itza.

The Mayans used the pigment in art and in rituals to bring the rains. Recent evidence suggests they painted sacrificial objects and human victims blue and threw them down a deep natural well called the Sacred Cenote, thought to be the home of the rain god Chaak.

The pigment was made by burning incense made from tree resin and using the heat to cook a mixture of indigo plants and a type of clay called palygorskite. A bowl retrieved from the Sacred Cenote revealed traces of all of these materials, each of which was considered to be a healing substance by the Mayans.

"By offering incense to Chaak, they were combining two healing components," said Dean Arnold, an anthropologist at Wheaton College in Ill. who examined the bowl. "This was ritually significant because the rain healed their land."

Now the physicists' X-ray beams and other measurements have revealed the secrets behind this recipe's remarkable longevity and durability. As the mixture was heated, indigo molecules filled a network of tiny channels inside the clay. Some of these bits of indigo plugged the pores on the surface, preventing the color from escaping over time.

The clay, in turn, protects the indigo from the environment. Harsh chemicals can destroy a sensitive bond within indigo molecules -- changing the color from blue to yellow. Like the double-parked car that prevents you from opening the driver-side door to your own car, the clay channels take up the space around the bond, blocking these chemicals.

After looking for other kinds of clay-like materials with similar structures, Dooryhee and colleague successfully combined indigo with a porous substance called zeolite -- widely used in commercial products as diverse as cement, laundry detergents, nutritional supplements, and cat litter -- to make a new kind of long-lasting blue pigment.

The team hopes to use this new material to restore paintings and is considering other applications such as colored cement, said Dooryhee.