(CN) – At the height of the Abbasid empire in the mid-ninth century, the palace city of Samarra was lavishly decorated with glass. Colorful tesserae, purple millefiori, and small perfectly translucent shapes adorned the walls, meant to inspire a sense of wonder and awe and perhaps even remind visitors of Solomon’s crystal palace.
A study published by PLOS One on Wednesday reveals new insight into where some of Samarra’s famed glass was manufactured in a “radical reinterpretation of the scale and sophistication of production and interregional trade of glass during the ninth century.”
The study was funded by a British Academy Small Research Grant and the European Research Council.
“Glass is a very fascinating material on so many levels … it is produced on a very large scale and it was traded widely so we can literally follow trades, economic and other exchange networks in the first millennium,” said Nadine Schibille, a research scientist at the National Center for Scientific Research in Orleans, France, who led the study. “To me it’s more interesting than ceramics because it’s a high-temperature technology and needs more specific skills, and well, anyone can make pottery.”
Schibille and her team studied 265 pieces of glass from three different museum collections, ranging from simple items to “sophisticated vessels with pinched, stamped, engraved, or linear wheel-cut decorations.”
Using lasers to remove micro-samples, researchers ionized the particles in plasma at 8,000 degrees Celsius. The samples were then analyzed with mass spectrometry revealing their chemical makeup.
Through this technique, researchers uncovered the raw materials used in the making of each glass artifact and where they came from. The study identified 58 elements and sorted most of the artifacts into two clear categories: glass containing high levels of potash and magnesia, likely made with soda-rich plant-ash, and glass with low levels of potash and magnesia, likely made with soda from a mineral source.
A third category holds several miscellaneous items that fit neither pattern.
These “soda-lime silica glasses (are) typical of late Byzantine and early Islamic assemblages from the eastern Mediterranean and Mesopotamia,” the team found.
Most of the tesserae was imported from Syria-Palestine or Egypt, whereas other glass samples were likely manufactured nearby, showing “the diversity of the Abbasid glass industry and the existence of deliberate production strategies.”
While many historians postulate that glass was manufactured in medieval Samarra, without archaeological evidence of furnaces or workshops this remains a subject of debate.
Samarra was founded on the eastern bank of the Tigris River in 836 A.D. by al-Mu’tasim, the eighth Abbasid caliph or emperor. At the peak of its power, the Abbasid Empire stretched from Uzbekistan to India.
Samarra “was a military encampment. That’s what it means by palace city in this particular case, it was like these large U.S. bases in the desert down in Arizona,” said Alastair Northedge, a professor emeritus at the University of Paris who has spent much of his life studying Samarra.
Built from beaten earth and adobe-style mud bricks, at 58 square kilometers Samarra remains the largest dense city to have survived from the time period. For more than 50 years, Samarra served as the empire’s capital city until the role was returned to Bagdad in 892.
Mesopotamia, Northedge said was “one of the earliest countries in history to use glass on pottery, or glaze on pottery, which seems to have happened about the same time as China.”
Since the beginning of the Iraq War in 2003, the United Nations Educational Scientific and Cultural Organization (UNESCO) reported the site of the ancient palace city “has been occupied by multinational forces that use it as a theatre for military operations.”
In addition to the bullet holes that now decorate the palace walls, the al-Askari mosque, a nearby Shi’a holy site, was bombed in February 2006 and June 2007.
“Hardly any work has been done in Iraq for many decades because of the difficulties of going there. With Saddam Hussein and the sanctions of the war and the occupation after 2003, lots and lots of difficulties have discouraged people from working there which means there’s lots of details to check,” said Northedge, who last visited the archaeological site in 2017.
“It was a little bit dangerous, but archeologists do that. You can’t be a good archeologist and stay safe,” he reflected. “You have to take some risks and you accept it.”