An Alabaster Alabastron

An archaeological excavation demonstrates the complementary skills of archaeologists and conservators and many others.  Archaeologists are experts in the history and material culture of a site, while conservators are knowledgeable about the materials and techniques used to create art and artifacts as well the steps needed to conserve and restore things. 

The fragments of this alabastron, a container made of alabaster or other materials for holding scented oils, were recovered in several different loci (excavation units) over a few years of excavations.  The archaeologists recognized the significance of the find and gathered the pieces together. 

Before Treatment

 

Then pieces were then given over to conservation.  After examining and documenting the fragments, I reconstructed the vessel using my favorite adhesive, Acryloid B-72, poly(ethyl methacrylate).  If the alabastron were going on display in a museum, I might have filled the gaps between fragments, possibly with a mixture of B-72 bulked with fumed silica or glass microballoons.  But like on most archaeological excavations, the goal of the conservator is to only stabilize the artifact and make it available for research.  Therefore, replacement of the losses is unnecessary.  Here is the finished alabastron.

After Treatment

Now the object is ready to go back to the archaeologist, who will draw and photograph the object and continue research on its significance.  An alabastron as large as this one (9 cm in diameter and over 13 cm in length) was probably imported; archaeologists can use the find to develop theories about trade and social interactions.

Preventive conservation at Gordion

Welcome back to another season of Objects Conservation at Gordion.  The team this year is Jessie Johnson, Cricket Harbeck, Julie Unruh in a cameo appearance, and me, Elizabeth La Duc, a graduate student in art conservation at Buffalo State College.  This is my first season at Gordion, and I’m very excited to be here.

In addition to active treatment of finds, a major part of our work is preventive conservation, including maintenance of proper storage conditions to reduce future degradation.  One annual task is renewing the bags of silica gel at the artifact storage depot.  Silica gel is used as a dessicant, just like in those little packets that come with new shoes.  (Silica gel can also be “conditioned” and used as a buffer to maintain a certain humidity).

Silica gel beads

Bags of silica gel are placed with groups of copper alloy artifacts in archival boxes.  Like many degradation reactions, bronze disease, a nasty form of copper corrosion caused by the presence of chlorides, is moisture dependent.  Left untreated, “infected” objects will disintegrate to green powder.  The silica gel maintains a dry environment inside the box, preventing further copper corrosion.  As mentioned in an earlier post, copper alloy objects at Gordion are routinely treated with BTA, a corrosion inhibitor, but a dry environment provides another layer of protection. 

Every year the silica gel bags are taken out and are dried in an oven to renew their moisture absorbing properties.  Some of the silica gel even includes an indicator that changes color when dry.  This year, we have an exciting new purchase for the lab: a new toaster oven.  It’s sold to make borek, a delicious Turkish pastry, but it is working well for silica gel, too. 

Unfortunately not for making pide (Turkish pizza)

Here’s the finished result: the indicator strip placed in the box with the renewed silica gel shows there’s no moisture and that the copper alloy objects are safe for another year.

A dry storage container

Site Conservation at Gordion

Gordion site conservators at work. Photo by Andrea Berlin.

An average visit to Gordion will include three stops: the museum, the Midas Tumulus, and the site located on the mound. For the last few seasons, Frank Matero and his students at the University of Pennsylvania programs in Architecture and Historic Preservation have been diligently working on preserving the site.

This season, site conservation projects include the installation of viewing pavilions, documentation, soft capping, and stabilizing the stone walls of the site. Objects conservation intern Lily Doan was able to join the site conservators for a day of injection grouting.

Here are some highlights from this season's site conservation projects:

The viewing pavilions, constructed from locally purchased
metal pipes and fabric, provide much needed shade for
visitors to the site.

UPenn students document the site. Photo by Andrea Berlin.

Locally produced mud bricks drying in the hot Turkish sun.
These bricks are a component of soft capping, a system where
the introduction of moisture, which may cause damage to the
stone walls, is regulated with plants installed on top of the wall.

Site conservator Alex Lim sifting lime in preparation
for grouting. Photo by Andrea Berlin.

Meredith Keller, site conservator, mixing the grout.

Objects conservator Lily Doan uses an air compressor to 

clean cracks in preparation for grouting.

Tomb Monkeys

The entrance into the Midas Tumulus

In addition to working on the artifacts in the Gordion Museum and in storage we also do some work in the fabulous wooden tomb chamber inside the Midas Tumulus. The Midas Tumulus is one of the archaeological resources open to the public in and around the village of Yassıhöyük.  Located across from the Gordion Museum it gets up to 60,000 visitors every year.

This year there are been a project to view features on pitched roof of the tomb and we have been working with the archaeologists who are carrying out the project to document the activity.

Documenting work on the roof of the 2700 year old tomb

Working on and around the tomb chamber involves some rather acrobatic maneuvers. Also being inside a fence and at times viewed by visitors gives a rather interesting flavor to the work- thus the term "tomb monkeys" has developed to describe the archaeologists working in the tomb day after day.

Silverback tomb monkey imparting advice to his assistant

We are also continuing environmental monitoring of the tomb to ensure that visitation, archaeological documentation activities and any unknown problems don’t create an environment that would endanger the wooden structure. This project, on-going for over a decade, has shown that there are small changes in temperature and environment that track what’s going on outside. The changes are slight and the ancient wooden structure (so far) is not in any danger from theseagents of deterioration.

Looking at 2010-2011 datalogger data

Tomb monkeys headed home after a long day 

Road Trip to Hittite Sites

From left to right:
Cybele Tom (NYU Conservation Program, Sardis Conservation Intern)
Jessica Pace (NYU Conservation Program, Sardis Conservation Intern)
Alex Lim (Research Fellow, UPenn Architectural Conservation Laboratory)

Lucas Stephens (Doctoral Student, UPenn AAMW Program)

The "weekend" at Gordion, which is from Wednesday afternoon until Thursday, is a good time to venture beyond the dig house and explore other areas of Turkey. Last weekend, Cybele Tom and Jessica Pace, conservation interns at Sardis, an archaeological site in Southwest Turkey, joined Gordion team members on a visit to several Hittite sites located in Central Anatolia.

Yielding to a flock of geese on our way to Hattusa.

The trip began with a tour of the Gordion site, tomb, and museum, as well as Dua Tepe. After lunch at the Gordion dig house, we set out on a road trip to the city of Bogazkale, where we stayed at a charming hotel and enjoyed a lovely dinner in a restaurant with Ottoman style furnishings and a stone fireplace.


The Hittite sites and museums we visited include Hattusa, Yazilikaya, and Alacahoyuk. This group of students and recent graduates included three objects conservators, an architectural conservator, and an archaeologist, which made for very interesting, and interdisciplinary, conversation regarding the sites and museums.


Here are a few highlights from our trip:

Dua Tepe. A memorial dedicated to the Turkish War of Independence.

Reconstruction of mudbrick walls of Hattusa, capital of the Hittite Empire.

The amazing landscape that surrounds Hattusa.

The reliefs of Yazilikaya, a sacred site of the Hittites.

The gates of Alacahoyuk, a Hittite settlement.

Our adventure ended in Ankara, where the two groups separated and returned to their respective sites. We would like to thank our friends from Sardis for joining us on a wonderful trip!

Saf Su (Pure or Distilled Water) at Gordion

Our goal: obtaining saf su.

Distilled or deionized water is important in many treatments completed here at Gordion Excavations. Therefore, one of our first and top priorities is obtaining an appropriate source of water, which proved to be quite a challenge this season. We first attempted the deionizing columns left over from previous years, but after several rounds the conductivity of the resulting water was off the charts.

Discussing the deionizing column with a chemical salesman in Ankara.

During a trip to Ankara, we ventured on a mission to find a local source for purchasing deionizing columns. The set up for purchasing chemicals and supplies in Ankara is rather amusing. In one section of town, there are a few strip malls with stores that sell medical, laboratory, and chemical supplies. In many ways, the experience feels like purchasing a car. The chemical salespeople contemplated the column: they tapped it, shook it, sniffed it, then called in reinforcement, who also tapped it, shook it, and sniffed it. After several visits to different stores, many confused looks, and a few phone calls, we were unsuccessful in locating a column.

Angie sets up the still outside of the lab.

Defeated in our quest for a deionizing column, we set up the still back at the lab. Although the process is slow, after several days of running the still, we were able to obtain enough distilled water for the season. In case we run out, several small bottles of distilled water were purchased from a petrol station in Polatli, a nearby town.

Feeling sorry for the water-deprived objects conservators, Gordion
archaeologists purchased these cute little bottles of distilled water.

Perhaps next season will be more successful in the quest for purchasing a deionizing column in Turkey - a tip from an Ankara local suggested home improvement stores that may carry water filtration systems designed for the home.

With saf su in hand, Gordion objects conservators commenced with desalination and other treatments involving water.

Soccer and Mulberries in Yassihoyuk

The Yassihoyuk mosque.

One afternoon, during our walk to the museum, we passed by the Yassihoyuk mosque. The courtyard of the mosque was filled with children from the village. We stopped to say hello and practice our Turkish. I do believe one boy said "Your Turkish is bad." Children are so honest.

Soccer in the mosque courtyard.

Angie joins the soccer game.

The children began a game of soccer, and we decided to sit in the shade of the courtyard and observe. Angie couldn't resist joining the game. A couple of the kids were standing on the wall, picking some fruit off a nearby tree. We stopped to get a closer look, and saw some white mulberries ripe for the picking! While we tried to figure out which berries were best to eat, an older village woman came out help us. The next 15 minutes were spent eating handfuls of delicious, juicy mulberries she picked for us. What a wonderful afternoon break, before heading back to work at the lab!

Delicious mulberries.