Thorny Oyster

 Author's note: To see an earlier post that lists different kinds of shells the ancient Maya used, click here.

Spondylus carving of a dog from the 600s to 700s AD.
May have been attached to clothing or been a pendant.
Courtesy of the Metropolitan Museum of Art.

The thorny oyster (Spondylus princeps) is a creature with a red to red-orange spiny shell that sometimes produces pearls (another item the ancient Maya valued). Also known simply as spondylus, it lives in the ocean around a depth where divers without expert ability or scuba equipment would have difficulty getting to.  Used in different ways, the shell of the thorny oyster obtained elite status level by the finish of the Classic Period.

Working the Shell
Thorny oyster shells were altered in a number of ways. One of the ways was to rub young thorny oysters to make the colors of the shell stand out. This method was employed at Tikal, during the early Classic and Middle Classic periods.

Another method of alteration was to scrape off the nacre found on the shell's interior sides. As to where all this method was used, some contradiction has been found. In her book, Animals and Plants of the Ancient Maya: A Guide, Victoria Schlesinger states that this method was used at Tikal, while Maya Art and Architecture by Mary Ellen Miller does not state it was restricted to any city-state.

A third known method was very simple indeed. This method involved just drilling a hole through the shell. This hole was to be used for stringing.

Things Fashioned from Thorny Oyster
Once prepared, the shell would then be used to decorate rulers' mantles, shaped into tiles for mosaics, crafted into ear flares (spool-shaped earrings) and used to make hip ornaments for women. Sometimes thorny oyster was worn as a pendant necklace (via the one-hole method). Beyond personal adornment, thorny oyster was also used as part of funeral goods and in caches.

References:
"Maya Art and Architecture"; Mary Ellen Miller; 1999
"The Ancient Maya: New Perspectives"; Heather Irene McKillop; 2004
"Maya History"; Tatiana Proskouriakoff; 2011
"The Meriam-Webster Dictionary"; 2004
"Animals and Plants of the Ancient Maya: A Guide"; Victoria Schlesinger; 2001
Metropolitan Museum of Art: Canine Ornament

Shells for Appearances

This pendant was made between the 600s AD and 700s AD, in either
Mexico or Guatemala. From the Metropolitan Museum of Art.

From personal adornment to ritual use, left whole or cut into shapes, the ancient Maya utilized different kinds of shells in their artistic and religious endeavors. Shells that we know the Maya used include the shell of the thorny oyster, the oliva, the conch and the pecten, among others.



Thorny Oyster
This oyster has a spiny shell, whose specific shade ranges from a red to a red-orange. The ancient Maya used the thorny oyster to make a whole range of items, from jewelry to cloak decorations. It became a more elite level shell by the Classic Period's close. (For more, go to the post on spiny oyster here.)

Oliva

These shell earflares were from either Mexico or Guatemala and
were made between the 300s AD and 900s AD. They both
have an image carved into them, with pigment inserted into
the carved lines. From LACMA.

Ancient Maya kings used the oliva shell in a certain kind of costume in which they wore strands of them -- these strands are thought to have made noise as they moved. For example, Yikin Chan Kawil (also spelled Yik'in Chan K'awiil), a king of Tikal during the 700s AD, can be seen in Tikal's Stela 5 wearing oliva shells. In contrast to the thorny oyster, by the Classic period's close the oliva shell was utilized by non-elite Maya in their adornments.

Conch
When it comes to the conch, the ancient Maya used several species for their shells. One species they turned into a kind of trumpet via altering the shell's lip, and then decorated -- by carving it, for example. Two other species have been found at sites carved into discs -- possibly items of personal wear. Like the oliva shell, at the finish of the Classic Period, conch shells were also a shell used by non-elites in their adornment.

Pecten
This shell's appearance is that of the quintessential scalloped clam shell. Introduced from Central Mexico, pecten shells were in favor in the Early Classic Period. Examples of pecten shells in art can be seen on Stela 4 at Tikal, in which the ruler is wearing a necklace of pecten shells -- an item seen in Teotihuacan art.

Other Shells
Two other kinds of shells were used, at least by the Classic Period's finale, by people of the non-elite class. These are the shells of freshwater mussels and pearly oysters, used by people of non-elite status for personal adornment.

Consideration
There are instances where, though a site is near a large body of salt water, the site's residents seem to have favored another body of salt water. One example of this is that most of the shells and other saltwater items at Tikal come from the Gulf of Mexico, not the Caribbean Sea. Another example is at Copán, where the Pacific Ocean seems to have the been preferred source of saltwater items.

References:
"Maya Art and Architecture"; Mary Ellen Miller; 1999
"The Ancient Maya: New Perspectives"; Heather Irene McKillop; 2004
"Maya History"; Tatiana Proskouriakoff; 2011
"The Meriam-Webster Dictionary"; 2004
"Animals and Plants of the Ancient Maya: A Guide"; Victoria Schlesinger; 2001

Image Credit:
Metropolitan Museum of Art: Bird Ornament

LACMA: Ear Flares with Incised Faces

Maya Blue

This figurine is partly painted with Maya blue. It was made in the
600s AD to 700s AD. It may represent a being that you may see
called the "Fat Man." (This figure seems to have been in part of
Mesoamerican cultures, and was connected, it seems, music as well
as comedy.) From The Metropolitan Museum of Art.

Used by the ancient -- and Colonial Period -- Maya (and other Mesoamericans), Maya blue is a pigment that is noticeably resistant to deterioration. After numerous studies (beginning in the early 1900s), it is now thought that at least two things went into its making: indigo dye and a kind of clay, either sepiolite or palygorskite. This article will focus on Maya blue's composition, production, resistance and its uses.

Historical Note

Maya blue has been found within the context of the Late Preclassic. However, it is in the Late Classic that increased usage of Maya blue began. During the beginning of the Late Classic, the use of Maya blue appears to have become common in the Usumacinta region, the Puuc region and Guatemala. The ancient Maya used the pigment through the Postclassic Period and even in the Colonial Period -- though its use declined and disappeared during the latter (around the end of the 1500s).

Color

Maya blue ranges in color from a light blue to green blue, and adjectives connected to its description include "vivid" and "radiant".  The color might be connected to iron as well as iron oxide nanoparticles, though it is also possible that it isn't -- an alternate theory being that it is the ratio of indigo dye to clay. Different shades may have been possible through different kinds of Maya blue recipes.

Indigo Dye

The genus Indigofera has species that can be used to produce indigo dye. The indigo dye the ancient Maya used could have come from different species, such as Indigofera suffruticosa (a shrub whose other names include Guatemala indigo, ti cafe, añil, wild indigo, añil de pasto or just indigo.

As for the way the ancient Maya made their dye -- that has yet to be discovered, and is therefore one of the lingering mysteries of Maya blue. For example, whether or not the dye was a liquid or reduced even further into chunks of dye (which would be ground up). 

The Clay -- Palygorskite or Sepiolite?

This is a rattle and whistle painted with Maya Blue that was
made in the 700s AD. From The Metropolitant Museum
of Art.

Of the resources thus far found in researching Maya blue, most tend to favor palygorskite as the clay that was used; (though some also include sepiolite in their definition. One book, Developments in Palygorskite-Sepiolite Research, states that sepiolite sometimes is found in Maya blue from the Aztec area.)

Also called attapulgite (an older name), palygorskite is defined by Encyclopedia Britannica Online as a fibrous magnesium aluminum silicate. It is a clay whose molecular structure is described as "fibrous", a kind of structure that has "channels" (or tunnels, as Handbook to Clay Science describes them). The "fibrous" structure, it is understood, is necessary for making Maya blue.

Production

It is now thought that it is not enough to mix indigo dye and palygorskite together -- the mixture has to be heated (Handbook says it must be 302 Fahrenheit), and for a couple of days.  As evidence, dehydroindigo (oxidized indigo dye) has been found in Maya blue, which may have formed when heated. Also, a blue color was only obtained, in studies I have found on creating Maya blue, when something else was added (such as acetone or diluted hydrochloric acid), so it is possible the ancient Maya had an acid or acids they could use.

How does the indigo dye bind to the clay?  It is thought that the dye is caught in the channels (or tunnels) of the palygorskite, perhaps at the ends of these channels. 

Resistance

A word connected to Maya blue is "stable". It is resistant to many things. For example, The Field Museum's Dr. Gary Feinman states that, "Maya blue is a very stable pigment. In other words, it does not rub of or wash off very easily." (Author's transcription.)

But Maya blue can resist more than rubbing and washing. Published in 2009, Electrochemical Methods in Archaeometry, Conservation and Restoration gives a list of things Maya blue can withstand. The book states that Maya blue is resistant to "...acids, alkalis, oxidants, reducing agents, organic solvents or biodegration."

How long can Maya blue resist attack? A study conducted by Rutherford J. Gettens involved putting samples of Maya blue from an incense burner in various liquids, including concentrated hydrochloric acid, concentrated sulfuric acid and concentrated nitric acid. After eighteen hours had passed the samples were still the same color.

Uses

The ancient Maya used Maya blue artistically for their murals, such as the murals at Bonampak, and figurines, such as those found on Jaina Island. Maya blue was also used as part of the color palette in codices. Also, it seems, they used it when preparing people and inanimate objects off as sacrifices.

What was the connection between Maya blue and making sacrifices? The understanding is that votives were covered with the pigment before they were sacrificed. As evidence, at the bottom of the Sacred Cenote, a layer of blue silt was found while it was being dredged. Dr. Feinman states that coating objects (and people) in Maya blue was an act used when making sacrifices to rain deities.

Consideration: Copal, A Potential Ingredient

A theory also exists that Maya blue was made by using burning copal resin to bind the indigo and palygorskite. According to Developments, it is yet to be seen whether or not Maya blue could be created by adding palygorskite-indigo dye mix to melted copal -- which melts below 302 degrees Fahrenheit.

References: 

"Handbook of Clay Science"; F. Bergaya, B.K.G. Theng, G. Lagaly; 2011

"Pigment Compendium: A Dictionary of Historical Pigments"; Nicholas Eastaugh, Valentine Walsh, Tracey Chaplin, Ruth Siddall; 2012

"Developments in Palygorskite-Sepiolite Research: A New Outlook on these Nanomaterials"; Elsevier; 2011

"The Archaeology of Science: Studying the Creation of Useful Knowledge"; Springer; 2013

"Electrochemical Methods in Archaeometry, Conservation and Restoration"; Antonio Doménech-Carbó, María Teresa Doménech-Carbó, Virginia Cost; 2009

"Analytical Archaeometry: Selected Topics"; Howell Edwards, Peter Vandenabeele; 2012

USDA Forest Service: International Institute of Tropical Forestry: Indigofera suffruticosa P. Mill.

The Field Museum: Science at FMNH : Ep. 42 – The Production of Maya Blue

The Field Museum: Dr. Gary Feinman

The Metropolitan Museum of Art: Crocodile Rattle

The Metropolitan Museum of Art: Costumed Figure

Image Credits:

The Metropolitan Museum of Art: Costumed Figure

The Metropolitan Museum of Art: Crocodile Rattle