I just wanted to share a photograph from Kemalettin who took a moment out of his busy work schedule to appreciate the colorful arrangement of tags and boxes awaiting his attention. We use the colored tags to prioritize our finds as they come in from the field. The depot count is at 229 crates with 22 working days left! Now back to work.
Press release for tokens research.
The University of Cambridge just released a press release about some of our on-going research spearheaded by John MacGinnis and recently published in the Cambridge Archaeology Journal.
The link to the press release is here.
This element of our research focuses on a collection of “tokens”, small clay artifacts in simple geometric shapes that were used to account for commodities such as sheep, cattle, and grain. This technology first appeared during prehistoric periods in the Near East and, as demonstrated at Ziyaret Tepe, continued well into the time when cuneiform documents were being used in the Iron Age. The press release provides a summary of our research and explains how these important, and often overlooked, artifacts were used.
The full citation for the reserch article is: MacGinnis, J., M. W. Monroe, D. Wicke and T. Matney (2014) “Artefacts of Cognition: the Use of Clay Tokens in a Neo-Assyrian Provincial Administration” Cambridge Archaeology Journal 24(2): 289-306.
One of our big projects this year is the conservation of three large fragments of an Assyrian wall paintings discovered by Dirk and his team in the Bronze Palace in 2008 and 2009. The Assyrians typically decorated their palaces with ornate figures and geometric designs. In the Assyrian heartland of modern-day northern Iraq, at places like Nineveh, these decorations were made by carving enormous flat panels of limestone called orthostats which lined the interior walls of the public buildings.
Here is an orthostat now found at the British Museum showing the Assyrian king hunting. These are some of the most stunning and iconic images we have from ancient Assyria.
Out on the northern frontier, at places like ancient Tushhan, palaces were not so elaborately adorned and wall paintings or frescoes were used in the place of carved stone orthostats. The paintings were made on white plaster with black, red, and blue paint. Because they are made from perishible substances, almost all of the wall paintings at Tushhan and other Assyrian imperial centers have been lost over the past 2700 years.
In 2008 and 2009, we found several large fragments that were preserved when the walls of the palace collapsed in upon themselves and sealed the plaster beneath the rubble of the mudbrick walls. These photographs from 2009 show Dirk carefully cleaning the surface of one of the paintings, and below that two of our conservation team, Charlotte Rerolle and Yvonne Helmholz, using a chemical consolidant to hold the plaster together so it could be lifted in one piece.
Because they were so delicate, we decided to lift the large fragments intact with the goal of conserving them in the laboratories of the Diyarbakir Museum in a later season. This was done by first digging the soil out from around the fresco to raise it above the surrounding ground level, a technique called pedestalling. Next we wrapped the edges of the fresco fragment in a non-adhesive covering akin to kitchen plastic wrap. Then we covered the entire perimeter in gauze bandages soaked in plaster to create a hard plaster shell around the fresco to give it stability.
Finally, an iron sheet was driven beneath the fresco, slicing through the soil pedestal, freeing the large fragment, which allowed us to remove the entire piece intact. Additional supporting material was added to the fragment before it was loaded on a truck and moved first to our depot, and then on to the Museum storeroom. By the time we were done, each of these “eggs”, as we nicknamed them, weighed enough to require a number of Turkish workmen to lift on poles.
Fast forward to 2014. The “eggs” have been sitting in a storage room in the Diyarbakir Museum for years awaiting our attention and finally this year we have a team of three conservators – Yvonne who was here in 2009, Lourdes Mesa Garcia, and Olga Emgrund – whose job is the crack open the eggs, clean them, and prepare them for exhibition. Here is what one of the plaster frescoes looked like at the beginning of the 2014 season. Yvonne has cracked open the first egg and is gently brushing away the dirt. The process of conservation will take weeks, or even months, before the wall fresco is stable enough to be put on display.
We will keep you up on progress on this conservation project. Wait and see!
A sprint to the finish.
Normally archaeology is like a marathon; slow and steady progress and lots of repetive tasks which require stamina and time. This season we have a goal to process 828 tomato crates full of pottery (the tomato crate is a standard measure of pottery in this part of the world, see photograph below). Every once in a while, however, you just feel like sprinting…
This morning four of our ceramicists took off in the car for the depot right after our morning tea at 5:30am, with scales, notebooks, and pens in hand to see if they could process all the pottery from two very large deposits in one morning. All before lunch! This is the ceramic equivalent of the 100m dash.
Here’s the before picture showing Marie Jensen, Raffaella Pappalardo, Azer Keskin, and Valentina Vezzoli standing in front a pile of pottery, most dating to the Late Assyrian period (9th – 7th centuries BC). Each bag represents the pottery excavated during a single day from a specific locus (a locus is, in effect, a well-defined spatial unit representing perhaps a pit, floor, or oven). The tags tell us which loci are stored in which tomato crate (stored in numerical order in the depot). So all of the pottery in each bag can be placed back to its exact spatial coordinates on the site plans. This pottery was washed when excavated but otherwise needs to be categorized prior to analysis.
Our ceramics team spent the morning separating the sherds into ware types (just like modern pottery which comes in different wares – bone china, earthenware, etc., so ancient potters used different clays for different purposes), counting and weighing the sherds from each locus and recording details of decoration, vessel construction, and use. Likewise, the ceramicists will also record the “form” (our term for shape), since the form of the pottery determines both its function (for cooking, eating, drinking, storage, etc.) and also its date. Just like in the modern world, pottery styles change through time providing experts like Marie, Raffaella, Azer, and Valentina with evidence for when the pots were made.
Just before lunch, four very hot, dusty ceramicists returned from the depot having processed 17 tomato crates in under six hours. It was a great effort and satisifying for them to make such progress. By the way, they were all still smiling.
Pretty unassuming, right?
One of our conservators, Yvonne Helmholz, has made a potential interesting discovery during the routine cleaning of an artifact destined for the study collection at the Diyarbakir Museum. The artifact is a flat bone plaque, roughly rectangular in shape. It is small, roughly 7.5cm by 5cm (3 inches by 2 inches) in size. Here is a picture of what it looked like when it came out of the ground.
Such objects are often used as decorative panels for wooden furniture such as chairs, tables, or beds. However, in this case, the bone appeared to be undecorated. Under the microscope, however, Yvonne discovered traces of very fine etching which may have the result of working the bone plaque into shape. More intriguing were minute traces of what looks like a very thin layer of metallic tin and a slightly thicker layer of gold on a few places. While we will need to undertake metallographic studies to confirm these initial observations, it seems not unlikely that this plain bone artifact may once have been covered in gold leaf. The tin, if that visual observation is confirmed by analysis, is more difficult to explain. Tin is often used as solder, but not with gold, so its function is unclear.
The plaque was discovered in Operation G in the lower town, in the corner room of wealthy residence. It was first discovered in 2003 and like so many artifacts that have been the subject of specialist analysis it has been waiting in line for final analysis. We are completing all of our field observations this year so there are certainly more interesting discoveries to come. After testing the metal residues, this interesting artifact is bound for the permanent study collections at the regional Diyarbakir Museum.
One of the more exciting elements of this year’s work is our collaboration with the regional Diyarbakır Archaeology Museum. There has been an archaeological museum in Diyarbakır since 1934 and the current building has been in use since 1985. The 1980’s building is now sadly in need of repairs and plans for opening a new cultural center, including a museum, in the old citadel (Iç kale) in Diyarbakır have been in the works for years and are nearing completion, so soon there will be a new home for all of the Ziyaret Tepe artifacts.
The new museum is in a spectacular old stone building on a high cliff overlooking the Tigris River at the edge of the city. The building has been restored as part of a complete refurbishment of the Iç kale. I’ll tell you more about that later.
Over the winter, Aytaç Coşkun, a craftsman working for the museum undertook a project to reconstruct a small portion of one of the large mosaic courtyards from the Assyrian public buildings excavated in the lower town. Here are some photographs of Courtyard 20 during excavation, a plan showing the location of three courtyards (2, 11, 20 on the plan), and a detailed photograph I sent to Mr. Coşkun, amongst other documentation.
The original mosaics were made with stones selected from the Tigris River and for his reconstruction, Mr. Coşkun also hand-selected hundreds of river stones of various sizes sorted into black and white groups to imitate the original materials. These stones were placed in a cement mortar (the Assyrians used a mud mortar) in the entrance to one of the two galleries dedicated to Ziyaret Tepe in the new museum. You can see his team at work below.
Mr. Coşkun used a movable frame for constructing each square of the mosaic. He started by lining the edges with flat cobbles laid on edge, as seen in the original Assyrian design. Next, he selected appropriately sized and shaped colored stones to fill in the interior spaces, moving on to the next part of the frame when the mortar had set. Unlike the cut stone tesserae that were used by later Roman craftsmen, Assyrian mosaics employed natural stone shapes.
The result is quite impressive and will give museum visitors a real sense of what the mosaics would have looked like in ancient times. The Assyrian originals were over 10m (30 feet) on a side, so this is just a sampling. (The wire sticking out is for lighting a small pedestal that will sit on the center of the mosaic.) Well done, Mr. Coşkun!
A new look.
Check out the new banner at the top of the page. This is a panaramic shot that Willis took of Bismil at night. One day shortly after we arrived in Turkey, six of us retired in the evening for some refreshments on the rooftop of the Hotel Dolay before dinner and were greeted by cool breezes and a full moon. For anyone who was in Bismil even a few years ago, you can see how the city has grown. The new census population is 111,000! The area is thriving with lots of new construction projects all over town in advance of the new Ilisu lake.
Our last digging season ended in a whirlwind of activity and I’ve been meaning to go back and finish off the last 2013 blog entries for months… and here it is 2014 already! As I told you last season, the 2014 season will be our last in Turkey. We are not going to be excavating this season on the mound or lower town, but we are still anticipating lots of interesting discoveries. Our goal this season is to fully process and record previously excavated finds stored in our depot in preparation for the final publications. This is the unglamorous side of archaeology – long hours in the laboratories – but very rewarding work.
A small crew arrived in Diyarbakir on Monday night and met with the new museum director, Mehmet Eneze, and our museum representative, Leyla Ay. Today, we opened our depots and set up a temporary field camp. On Friday, we will move into the local school that has served for the past two years as our field camp, but in the meantime we have accomodations at a hotel in Bismil. The garden will be a comfortable spot for a few days and here you see Jane, Tina, Emily, Tim and Azer (Willis took the picture) hard at work. With such a short field season (our last day is August 15) there is no time to waste! Check back in for our latest discoveries in the coming days.
A new element in our research.
This blog is written for my Materials Science students back at UAkron, who are busy learning some chemistry essentials with my co-instructor, Prof. Richard Elliott of our Department of Chemical and Biomolecular Engineering. A few days ago, we hosted two visiting scholars for a two day visit to Ziyaret Tepe: Prof. Thomas Zimmerman, the head of the archaeology department at Bilkent University and Dr. Latif Özen, a chemist and conservator in the Laboratory for Restoration and Conservation at the Museum of Anatolian Civilisations, both in Ankara. Thomas and Latif brought a portable x-ray fluorescence unit (p-XRF) to study the elemental composition of some of our artifacts.
In particular, we were interested in the metal artifacts found in the cremation burials in the Bronze Palace, which we assumed were made of copper alloys, most likely bronze (an alloy of bronze and tin). An artifact is placed on the sensor of the p-XRF and is subjected to a high energy x-ray beam. The sensor monitors the emission of energy by excited atoms on the surface of the artifact (to a depth of 3 microns); the specific characteristics of the energy emitted tells us what atoms are present.
In initial tests, we found that some of our ancient metal artifacts (not from the cremation burials) were nearly pure copper, while others were copper-tin bronze, and at least one was made of an alloy of copper and arsenic (called “arsenical bronze”). We also found that one team member’s “white gold” ring was nickel plated and that my 18K gold wedding band is actually 14K gold since the p-XRF provides a weight percent so we not only what elements are present, but their relative percentages.
Here’s the question for the Materials Science class. All of the artifacts tested initially by Thomas and Latif from the burials had very, very low concentrations of the element vanadium (V, atomic number 23). In their previous analyses of 1500+ artifacts from ancient Anatolia, they did not have evidence for the presence of vanadium in any artifacts and yet it was consistently present in all the artifacts from the cremation burial at Ziyaret Tepe that they initially tested. This was an unanticipated surprise. We subsequently tested earth samples of the burnt lining of two of the cremations and they too had a very, very low vanadium concentration, a few parts per million. In other words, this element is present in the edges of the cremation pits, not just in the metal artifacts.
So, UAkron students, what are some possible explanations for the presence of vanadium in these archaeological contexts and artifacts? What can you tell me about vanadium’s properties, occurence in nature, and the various states in which it occurs? The concentrations are a fraction of a percent, so it is a trace element in these artifacts.
Disclaimer: these results are only very preliminary and need statistical analysis to verify and to provide us with more precise estimates of the concentration. Likewise, Thomas and Latif continued their analyses after leaving the dig house, working in the museum until their flight home to Ankara, so there are some analyses for which I have no information about at all. It’s an interesting little chemistry puzzle for the beginning of the semester. I’ll pass along any other details as they emerge.
As you all know, Ziyaret Tepe is pretty well off the beaten path and it is a rare treat to have visitors to the site. As such, it was a real honor – or should we say, honour – for the team to greet the British Ambassador to Turkey, His Excellency Sir David Reddaway, who came a few days ago for a short stay to meet our team and tour Ziyaret Tepe and some other local places of historical interest. The reason for Sir David’s visit was not entirely archaeological, however. His son, Milo, has been working with us for the past three weeks and Sir David came to see Milo in action.
Milo is just entering the final year at King’s School Canterbury, an institution which was founded in 597 – contemporary with our own late Roman layers! He has a keen interest in archaeology and, we are delighted to say, this now includes the Assyrians. In addition to a great exposure to how archaeologists work in the field, the experience has also allowed Milo to complete the final requirement for his gold level Duke of Edinburgh Award.
Milo has worked most closely with John, but we also made sure that he got experience doing geophysical survey, working in the laboratories, in the sherdyard, and observing the specialists. Many archaeological field methods, as I often tell my undergraduate students back at the University of Akron, can only be learned hands-on at the excavation. Here Milo is getting some practice digging mudbrick, which involves experiencing the feel of the material and learning how the soil breaks apart from intact mudbrick under a small pick. The only place to become an expert excavator is in the bottom of a trench.