THE ‘AIN GHAZAL STATUE PROJECT

A group of Pre-Pottery Neolithic lime plaster statues are currently
undergoing conservation at the Institute of Archaeology.


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Neolithic ‘Ain Ghazal
The statues were found at the Neolithic site of ‘Ain Ghazal, in central Jordan during excavation in 1983. The site was initially discovered during the building of a new road in the 1970’s on the north-east outskirts of Amman and most excavation has been of a rescue nature, made necessary because of extensive development taking place in the area.

Excavation has produced information showing that the site, measuring approx. 30 acres was occupied for more than 2000 years as a farming settlement. ‘Ain Ghazal is thought to have been founded around 7250 BC in the mid pre-pottery Neolithic B and abandoned around 5000BC. Archaeological evidence gives an insight to the changes witnessed across three major periods:- Pre-pottery Neolithic B (PPNB), Pre-pottery Neolithic C (PPNC) and the Yarmoukian phase of the Pottery Neolithic.



The Statue Cache
The 1983 cache was a single, self-contained deposit buried with reasonable care in a flat-bottomed pit. The pit was found in a cluster of buildings. The statues could be seen to be overlying two superimposed plaster floors but the cache appears not to have been in direct stratigraphic association with any structure.

The statues have been divided into two categories according to their size: the smaller, approximately 35cm in height, are referred to as ‘Dumpies’ and the larger, approximately 90cm in height are known as ‘Figures". The dumpies consist of a solid base representing the torso which may be partly shaped but with little detail and usually no decoration, while the figures are larger with definite arms and legs. photograph All heads have been made with a great attention to detail and eyes, nose, mouth and ears are all depicted clearly. The eyes are elliptical in shape and where they survive, the irises are round and differ in diameter from statue to statue. The noses are very pronouncedly retroussé with the nostrils depicted as two incised lines, while the mouths are a simple horizontal slit. The ears are present as small protuberances often with a small central depression roughly impressed in them.

A rescue operation was mounted under the supervision of Kathryn Walker Tubb which entailed lifting the cache of statues intact and removing them safely from site. A traditional block-lift method was used in which the cache of statues was isolated on a pedestal of earth, covered with aluminum foil and packaged using polyurethane foam to cushion it and lock it in position within a pre-constructed wooden crate.
The cache was then detached from the pedestal of earth by undercutting it and was then inverted. This side was then foamed into position after the removal of the pedestal and a lid secured in place. The cache was subsequently transported to the conservation laboratories at the Institute of Archaeology for further treatment.

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The ultimate aim of the conservation process is the separation of the statues to ensure the stability of the individual pieces and to make available this unique collection for intensive study. Early work carried out included the excavation of soil from the exposed surface of the cache, examination of the technology of the statues, comparative typological studies, and the development of a treatment for the statues. Radiocarbon accelerator dates obtained from charcoal existing within the cache produced dates of 8660+/- 80 BP and 8700+/- 80 BP

The presence of a second cache was suspected in 1984 when material similar to that of the first cache was observed to be eroding out of the vertical side of a terrace cut in a slope of the site to take bulldozer traffic during construction of the motorway referred to above. Lifting could not be carried out until the following year and the exposed area was back filled to try to prevent deterioration in the intervening period. After excavation, the cache was transported to the Conservation Analytical Laboratory of the Smithsonian Institution, Washington D.C. The conservation treatment on this material is now complete and 2 of the 6 statues are on display at the Sackler-Freer Gallery until early April 1997.




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Technological Details
The statues had been made by modelling plaster made up of slaked lime, quartz and crushed calcareous filler on a reed/rush bundle armature. The armature was reinforced using spun twine/string. Impressions of the organic material are clearly preserved on the interior surfaces of the lime plaster and their interpretation yields a wealth of technological information. The cores in the dumpies consisted of a simple bundle of reeds which extended down through the centres of the bodies from half to three-quarters of their total heights leaving broad solid bases.
The cores of the figures were much more complex in their construction consisting of several bundles married together using twine to extend height and width. In both cases, the head and neck parts of the armature were reinforced by a close, continuous binding of twine. Evidence from the pit fill indicates the reeds extended through the base of the feet. These extensions could then have been embedded in the plaster floors, thereby securing the statues in a standing position.

Some statue surfaces were decorated with pigments: ochres, carbon black and a fine white lime plaster. The eyes were delineated using a bituminous mastic/putty as eyeliner, the same material was also used for irises. The eyeliner is further embellished in some cases with a green coloured pigment called dioptase, a hydrated copper silicate.







Condition
The condition of the statues is due to the inherent nature of the materials used, the conditions during long term burial and lastly and more recently, to the disruption to the site during the highway construction.

The plaster varies in the extent of its fragility from extremely fragile to relatively sound. It is seen that where the plaster of adjacent statues has been in intimate contact, not separated by even a millimeter of pit fill, presumed cycling of the calcium carbonate between carbonate and bicarbonate in response to moisture in the burial environment has resulted in the formation of a natural cement.

The reed/rush armatures previously mentioned are completely deteriorated now, and so not only is the support they imparted missing, the resulting voids render the statues far more vulnerable. The voids have either all but disappeared as a result of compression caused by the overburden of soil or are filled with a free flowing silt. Where the front and back of the statues have compacted, the plaster is virtually pulverized or has achieved a new shape through the myriad of fine cracks.

The cache was found approx. 1.5m below a terrace cut to allow the movement of construction vehicles and bulldozers along the side of the new road being built. The vibration and weight generated by the machinery was partially dispersed by the intervening occupation debris: however, the resultant crushing, cracking and breaking of the objects was severe.

It is important to note that during treatment evidence of pre-depositional damage has been found. Irises/pupils are often missing and, in no case are the fronts of feet in alignment. It is unclear whether this can all be attributed to wear and tear sustained in their primary location or whether it was this movement from their primary location for deposition in the pit that incurred the damage. It is most likely that both factors were contributory. Although most of the statues were virtually intact when buried, one, at least, must have been a jumble of fragments; two heads were broken in half and located in different positions in the pit and a few bodies with missing heads and vice versa are present. It is possible that headless bodies and bodiless heads may marry up as conservation proceeds.



Treatment
The consolidation system was chosen, among other reasons, for its ability to impart strength to the decayed plaster, to reach a reasonable depth of penetration and to allow re-treatment at a later date should this be required.

Consolidation was carried out using an acrylic-silane mixture. Initially the silane (Dow Corning Z6070 a methyltrimethoxy silane) alone was applied gradually across the surface of the statue using a pipette. Care was taken not to wet the plaster too much as this could result in smearing and therefore loss of surface detail. An acrylic and low molecular weight silicone mixture (Racanello E55050) was added to the silane in increments of 3,5,7,10,15 and 20% in order to confer greater strength to the plaster than the silane alone.

In areas where the plaster was extremely crushed, later applications of Paraloid B-72 (an acrylic co-polymer) of varying concentrations in toluene, have been applied directly to the surface as required to maintain cohesion of the plaster crumbs.

Support for the pieces of the individual statues was necessary during the separation and lifting procedure in order to preserve the pattern of alignment and so make reconstruction easier. Strips of an acid free Japanese tissue were attached to the previously treated surfaces using polyvinyl alcohol as the facing adhesive, which showed no adverse reaction to later silane application on the reverse. Further strapping was applied, where necessary, using masking tape over the surfaces protected by the facing.

Cleaning of previously unexposed surfaces was carried out using hand tools, under the microscope, prior to their acrylic-silane consolidation. Reconstruction was carried out and joins were created using Paraloid B-72 in acetone, as the adhesive. The statues, where possible were rebuilt around a new armature of Perspex rods. The spaces around the rods were packed with cotton wool to provide a tight and supportive structure. Any gaps which required filling for support and/or the aesthetic integrity of the piece was undertaken using a variety of material called BJK dough (a mixture of a synthetic resin, jute and kaolin, mixed with 5 solvents to produce a putty) and fine vinyl based calcium sulphate spackles. These areas of infill were toned in using either acrylic paints or dry powder pigments with an acrylic binding medium.



Current work
Treatment was restarted on a full time basis funded by the British Museum in 1994.



Further Reading
Rollefson, G.O. 1985 ‘The 1983 season at the early Neolithic site of ‘Ain Ghazal.’ National Geographic Research 1 p44-62
Tubb, K.W. 1985 ‘Preliminary report on the ‘Ain Ghazal Statues’ Mitteilungen der Deutschen Orient-Gesellschaft zu Berlin p117-134
Tubb, K.W. 1987 ‘Conservation of the Lime Plaster Statues of ‘Ain Ghazal’. in J Black(ed.) Recent Advances in the Conservation and Analysis of Artifacts. London p387-391
Tubb, K.W and Grissom, C 1995 ‘Ayn Ghazal: A comparative study of the 1983 and 1985 Statuary Caches’ Studies in the History and Archaeology of Jordan 5 ( Department of Antiquities, Jordan) 437-447

Information by Kathryn Walker Tubb and Susanne Ryder July 1997