from ‘Ain Ghazal, Jordan · 2016. 10. 3. · consolidated using 5% Paraloid B-72 in toluene. An...
Transcript of from ‘Ain Ghazal, Jordan · 2016. 10. 3. · consolidated using 5% Paraloid B-72 in toluene. An...
Conservation of a Neolithic plaster statue
from ‘Ain Ghazal, JordanSupervisors: Kathy Tubb, Institute of Archaeology, University College London, UK
Hans–Joachim Leithner, University of Applied Sciences, Erfurt, Germany
INTRODUCTION: A group of stunning anthropomorphic lime plaster statues was excavated at the
Neolithic site of ‘Ain Ghazal, Jordan in 1983 [1]. The statues, carbon dated to 8700 BP, were found
stacked on top of each other in a pit. Due to the complexity of the find the whole cache was carefully
block-lifted and transferred to the Institute of Archaeology, UCL in London for treatment. This poster
describes the conservation of one of the statues following initial consolidation and separation.
OBJECT DESCRIPTION: The bust-like figure has a stout body with an elongated slender neck that
carries a relatively flat head. Facial features are simplified, dominated by the eyes, which are large
and accentuated with a bituminous mastic. A broad ochre stripe runs across each cheek. The object
was modelled by applying calcareous plaster over a bundle of reeds secured with twine, which can be
reconstructed from well defined impressions of the plant materials in the plaster surface [2].
CONDITION: During burial the organic reed core had decomposed and the internal void thus created
had partly collapsed, causing severe fragmentation and deformation. The neck section was broken
into over 90 fragments and the nose is destroyed due to the pressure of an adjacent figure. The figure
was previously part-consolidated and protective bandages were applied to allow for its separation
from the cache [3]. The plaster was powdery and crumbling in non-consolidated areas. The surface
was soiled, particularly at the lower body where dirt had inadvertently been brushed in during
excavation. Considerable surface damage at the back of the figure appears to have been caused by
insects. The bitumen applications were missing on the left eye and extremely brittle where preserved.
The ochre pigment on the face was powdery.
CONSERVATION: Old protective bandages and internal soil were carefully removed. Thorough
mapping of the surface was undertaken for precise reconstruction. Loose fragments down to a size
of 3mm were transferred to 1:1 scaled photographs of the figure to facilitate later repositioning.
Particularly fractured areas were temporarily faced with gauze and Paraloid B-72. Surface cleaning
was carried out under 10x magnification, mostly with scalpel and needle. Fragile areas, such as the
ochre paint, were consolidated first using 5% Paraloid B-72 in acetone. In previously consolidated
areas cleaning was carried out mostly with a 1:1 mixture of acetone and IMS applied with cotton
swabs in a careful rolling manner. The front of the body with the brushed-in soil was successfully
Laser cleaned in collaboration with the British Museum. Powdery and crumbly plaster was
consolidated using 5% Paraloid B-72 in toluene.
An internal Perspex support structure was designed to allow vertical presentation of the figure by
taking the weight of the head off the fragile neck section. A bundle of seven Perspex rods of 3 and
4mm diameter were joined using dichloromethane and inserted into the void left by the decayed
reed bundle. The void was then tightly padded with polyester wadding to stabilise the Perspex rods
whilst preserving the internal impressions of reed and twine in the plaster. The support structure
was first fitted into the main body and head. The fragmented neck section was then carefully
assembled around the structure using Paraloid -B72. In missing areas small bridges of BJK dough,
a mastic from jute flock, polyvinyl butyral, kaolin and solvents, were applied and covered with a
smooth layer of glass micro-balloons in Paraloid B-72. The gap-filled areas were kept 1mm below
original level and painted slightly lighter than the surrounding areas using matt Windsor and
Newton acrylic paint. Bitumen applications that had become dislocated were re-attached using
Klucel G. To transfer the extremely delicate fragments, only the surface tension of a small wetted
cotton bud was used.
Liesa Brierley
Cache of statues still in-situ. The object discussed is
highlighted in red (photo: B. F. Byrd).
Preparations for block-lifting,1983 (photo: B. F. Byrd).
Particularly fractured areas during and after
conservation. Top left shows the temporary gauze
facing applied to hold fragments together.
Assembly of neck section around internal
Perspex support structure (photo: K. Tubb)
Re-attaching the embrittled bituminous
mastic of eye and pupilGap filling using a small spatula carved from
a cocktail stick
Application of glass micro balloons in
Paraloid B-72 (photo: K. Tubb)
Impressions of twine made from plant material
on the internal surface of the plaster fragments
Object after separation from cache, as received
for conservation treatment Map of Jordan - ‘Ain Ghazal is indicated in red
fragmentation
(more than 100
parts)
deformation and
loss
brushed-in soil
insect damage
powdery pigment
Eye applications
missing or brittle
surface powdery
and soiled
Schematic cross-sections of original and decayed statesMapping of damage
REFERENCES
[1] Rollefson, G. O., ‘The 1983 season at the early Neolithic site of Ain Ghazal’, National geographic research 1 (1985) 44-62
[2] Tubb, K. W., and Grissom C. A., ‘Ayn Ghazāl: a comparative study of the 1983 and 1985 statuary caches´, Studies in the history
and archaeology of Jordan, ed. Amr, K., Zayadin, F, and Zaghloul, M., Department of Antiquities, Amman 5 (1995) 437- 447
[3] Tubb, K. W., ‘Conservation of the lime plaster statues of ‘Ain Ghazal’, in Recent advances in the conservation and analysis of
artefacts, ed. Black, J., Summer Schools Press University of London (1987) 387-391
ACKNOWLEDGMENTS
I would like to thank my supervisor Kathy Tubb for
entrusting me with this object and her continuous support.
I am indebted to ‘Evangelisches Studienwerk e.V. Villigst’
for generous sponsorship during my studies.
Contact: [email protected]
Object after conservation