THE 'AIN GHAZAL STATUE PROJECT
A group of Pre-Pottery Neolithic
lime plaster statues which
have recently undergone conservation at the Institute of Archaeology
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. 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.
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.
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.
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
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