Spectacular green glass rods dug up in the ancient Egyptian city of Akhetaten and glass beads found in graves in Scandinavia, northern Germany and Romania, all originated in Mesopotamia, a new study has proven. The advanced analysis of the glass brings further proof to the existence of a vast trading system 3400 years ago, in which precious metals, amber and glass were exchanged.
The latest revelations, made by a team of scientists from Moesgaard Museum and the National Museum of Denmark, are the first archaeological evidence backing the "Amarna Letters", in which no less a dignitary than Pharaoh Akhenaten himself requests massive deliveries of glass from local rulers in nations around the Mediterranean.
They also reinforce recent studies proving the existence of a complex trading system of precious metals and stones from the far northern reaches of Scandinavia to Mesopotamia and Egypt during the Bronze Age.
The glass rods were originally found in the 19th century, in W.M- Fliders Petries' excavations of Tell Amarna, the site of the new capital built by Pharaoh Akhenaten, who ruled from 1353-1336. The city was abandoned after his death.
In a new analysis, taking a tiny proportion of glass found at Amarna, the team tested 13 pieces of rods of different colors, blue glass chips and glass shards with multicolor decorations, using plasma-spectrometry. Their conclusion was that the green glass rods had been made in Mesopotamia.
Like metal ingots, the glass rods were raw material. In this case they were used for fine glasswork, for instance decorating glass vessels and stoneworks, and for inlays in gold jewelry and wooden objects, such as coffins and furniture.
Glass was as highly valued in the Late Bronze Age as the precious stones lapis lazuli or turquoise, obsidian and amethyst.
Diplomacy in Akkadian
The Amarna Letters, a set of clay tablets in Akkadian, detailing diplomatic correspondence between ancient rulers in today's Syria and Egypt, show that Akhenaten was seeking significant quantities of Mesopotamian glass, despite the existence of glass workshops in his city Akhetaten.
Evidently, even though Egyptian glass manufacturing was significant in scale, foreign supplies were needed.
Thilo Rehren, professor of archaeological materials and technology at University College of London, explains that in his opinion, not every workshop was capable of producing all colors.
“Most colors needed special knowledge or special materials," Rehren tells Haaretz. "Access to and knowledge of these special minerals was limited, and may have driven specialization in the glass industry. Everybody was able to make simple copper blue glass - but the other colors are more specialist,” he says, and adds, “Why is Germany importing cars from Japan or France, when they have their own car-making industry?”
The exchange of glass between the main powers of the time gave them all access to the full spectrum of glass for their artistic studios, sparing them the need to maintain primary producing workshops with access to, not to mention knowledge of, all the exotic minerals needed for each color, Rehren argues.
A matter for the Pharaoh
The analysis provides the first solid archaeological evidence of glass trading between Mesopotamia and Egypt, which had been known beforehand solely from the Amarna Letters.
The letters show that the demand for glass was important enough to warrant the pharaoh’s direct attention.
In fact, Egypt was apparently already importing glass from Syria a hundred years earlier, during the reign of Thutmosis III (1479-1425 BCE), and he may have been personally involved too. The Annals of Thutmosis III, which can be viewed on the walls of the Karnak Temple, display how the glass flowed into the hands of the Pharaoh. A depiction of Thutmosis III donating tribute acquired from his Syrian wars to the Temple shows gold, silver and seven baskets with what seem to be precious stones to the Karnak temple – but three of these baskets mostly likely contain glass ingots.
“The glass depicted there does indeed most likely represent glass ingots. They are shown as circular pieces of fairly consistent size, whilst other pieces are shown as irregular lumps," Dr. Daniela Rosenow from University College in London and project curator of the Department Ancient Egypt and Sudan at the British Museum, told Haaretz. "The apparent raw glass is described as ‘Menkheperre lapis lazuli' ’to distinguish it from genuine lapis lazuli. Maybe the king was so impressed by this new material that he chose to add his throne name to it. While the deep blue glass is an imitation of lapis lazuli, the green glass shown as round cakes is referred to as Menkheperre turquoise/malachite."
175 Egyptian disk-shaped glass ingots, almost all blue, shaped the same as the ingots depicted at Karnak, were also found in the Uluburun shipwreck off the southern Turkish coast, which also dates to the late 14th century BC.
Mycenae, trading hub of the ancients
The team's chemical analysis of glass beads found in burials in Romania, Northern Germany and Denmark shows that they were also made from, or with, Mesopotamian glass, probably traded some time between 1400-1100 BCE. (Some were made of mixed Mesopotamian and Egyptian glass.)
Even though the origin of the raw glass used to make these beads can be determined as Egypt or Mesopotamia, determining where the glass beads unearthed in Europe were made is harder.
Secondary glass workshops would have reworked the raw glass, for instance mixing in Egyptian cobalt blue to create luxurious blue glass beads.
“Glass was a commonly traded object in the eastern Mediterranean world. It first appeared in Mesopotamia, but later it also was produced in Egypt. The glass was mostly traded as big 'round cheese' shaped ingots in that area. And probably, somewhere, glass workshops produced glass beads for trade in Europe. It could have been in the great trade ports such as Ugarit in Syria or most likely in Mycenae,” Dr. Jeanette Varberg, who is associated with the research and curator of Exhibits at Moesgaard Museum, told Haaretz.
Rehren is more cautious.
“The mixing of glass in secondary workshops is an interesting possibility, but I would need to see clearer evidence for it. There are some observations and analyses that could be interpreted this way, but more data and clarity is needed before I can see this as a regular pattern," Rehen says. "Mixing colored glass is a tricky business, since the colors bleed into each other and don't mix well. Glass mixing (and recycling) therefore is in my view really only starting with the emergence of colorless glass in the Hellenistic and Roman period,” he tells Haaretz.
In the East, raw glass seem to have moved along established trade routes via ports like Ugarit, reaching central places such as Mycenae
“Mycenae was the trade link to the rest of Europe. Amber beads probably went through there and the Mycenaeans were aware of the gold mines in Transylvania, copper mines in the Alps and the tin in South England, and most likely traded with them,” said Varberg.
From the Mycenaean central places, the trade routes were many. Also, glass beads are small. For the Mesopotamian glass to reach remote Alpine areas from the coast, all it took was one or two travelers slogging across the peaks with a thousand beads in a bag.
In Western Romania, beads made with Mesopotamian glassine elements were found in several burials and hoards. The most prominent is the Cioclovina Cave, which had 7500 artifacts of which 2325 were glass beads, 570 faience beads and 1770 amber beads.In Neustrelitz, North Germany a ceramic vessel containing 880 objects was found, with 20 amber beads and 179 glass beads.
Recent analysis of Danish glass beads has demonstrated that Mesopotamian glass is represented in 10 Danish burials. The most recent analysis of the chemistry of a blue glass bead from Puggegaard, Bornholm, has yielded yet another Mesopotamian result. The glass bead was found close to an amber bead in the burial of a woman, from 1400-1100 BCE. The grave also contained a bronze tutulus and bronze tubes for decorating a corded skirt.
Northern Germany was part of the amber trading network, Varberg says, and Romania had rich gold mines in the very same mountains where Cioclovina Cave lies.
Mesopotamian glass also reached the western parts of the Mediterranean in the 14th and 13th century BCE.: 25 glass beads were found at a rich burial at Campu Stefanu, Corsica, France. From Corsica, it is possible to follow the north-south routes of exchange through the Central Alps.
Following the north-south river systems of Europe and watersheds, there are a number of possibilities for connecting the Romanian find spots with Neustrelitz, not far away from the Baltic Sea, Bornholm Island, and the rest of Denmark.
The glass from the Neustrelitz hoard shows some of the same characteristics as the Romanian and the Danish material. It is thereby possible to follow the routes, almost step-by-step, from Mesopotamia to Denmark.
”It is impressive to be able to trace the flow of this glass across the whole of Europe, at such an early date. Numerous intermediate stops will have been needed for these beads to reach thus far - no need to focus only on the Mycenaeans as intermediaries, although they are of course the prime suspects,” Prof Rehren says and concludes, ”Similarly, and possibly in return, we see a lot of Baltic amber reaching the eastern Mediterranean - another precious stone that travels light and far.”