Hatfield Enclosure, Marden, Wiltshire: The conservation of block

RESEARCH REPORT SERIES no. 25-2013
HATFIELD ENCLOSURE, MARDEN, WILTSHIRE
THE CONSERVATION OF BLOCK-LIFTED
BONE AND ANTLER
ARCHAEOLOGICAL CONSERVATION REPORT
Angela Middleton, Diana McCormack, Fay Worley
INTERVENTION
AND ANALYSIS
Research Report Series 25-2013
Hatfield Enclosure, Marden, Wiltshire
The conservation of block-lifted bone and antler
Diana McCormack, Angela Middleton, Fay Worley
NGR: SU 0909 5819
© English Heritage
ISSN 2046-9799 (Print)
ISSN 2046-9802 (Online)
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SUMMARY
This report details the assessment and conservation of block lifted bone and antler from
Marden Henge, Wiltshire. The material was damp and in a very poor state of
preservation. The excavation from soil blocks was followed by consolidation and slow air
drying.
CONTRIBUTORS
Illustrations of selected small finds were completed by Judith Dobie, English Heritage, Fort
Cumberland, Fort Cumberland Road, Portsmouth, PO4 9LD
ARCHIVE LOCATION
Wiltshire Heritage Museum
DATE OF CONSERVATION
2012
CONTACT DETAILS
English Heritage, Fort Cumberland, Fort Cumberland Road, Portsmouth, PO4 9LD
Diana McCormack, 023 92 856778, [email protected]
Angela Middleton, 023 92 85 6787, [email protected]
Fay Worley, 023 92 85 6789, [email protected]
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CONTENTS
Introduction ...................................................................................................................................... 1
Lifting .................................................................................................................................................. 1
Assessment........................................................................................................................................ 2
Excavation and conservation of the bone/ antler..................................................................... 3
SF33733 ........................................................................................................................................................................3
SF33735 ........................................................................................................................................................................5
SF3062 ..........................................................................................................................................................................6
SF33731 ........................................................................................................................................................................8
SF33732 ......................................................................................................................................................................13
SF33734 ......................................................................................................................................................................13
SF33736 ......................................................................................................................................................................14
SF33737 ......................................................................................................................................................................16
SF33738 ......................................................................................................................................................................21
SF33743 ......................................................................................................................................................................21
SF33744 ......................................................................................................................................................................22
SF3061 ........................................................................................................................................................................24
Conclusion and recommendations ............................................................................................ 25
References....................................................................................................................................... 25
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INTRODUCTION
In June 2010 English Heritage, led by Jim Leary (Archaeological Projects) undertook an
investigation of Marden Henge, Wiltshire. Four trenches (A–D) were opened with the
overall aim of better understanding the prehistoric archaeology of Marden Henge (Leary
2010).
The material considered in this report originates from two distinct contexts, 92023 and
92024, both from within trench B, which focused on one terminal of the south eastern
henge enclosure ditch. The importance of organic material from this ditch was recognised
in a research questions relating to trench B: “Is there dateable material present within this
ditch? The paucity of potential samples to date the construction of the henge ditch from
the archive (due to conservation issues), means that recovering dateable material from
the ditch (antlers, organics, etc) may be the only opportunity to date the enclosure.”
(Leary 2010, 34). The importance of the material, including its potential for dating, had a
direct impact on the conservation work.
16 blocks were lifted on site with assistance from the project conservator Karla Graham.
12 of these blocks contained either bone or antler, and sometimes wood (Table 1). The
remaining 4 contained wood only and do not form part of this report.
LIFTING
The condition of the soil and the organic material made it necessary to block lift. The
prevalent clay caused a lot of movement when excavators walked across the site and only
allowed for superficial cleaning of finds in situ (Figures 1–2).
Figure 1: SF33734 in situ, superficially
cleaned
Figure 2: SF33731 in situ, superficially
cleaned
Artefacts were lifted en-block on a pedestal of, and with, the surrounding clay and
protected with cling film or tin foil. The blocks were then stored in the cold room at Fort
Cumberland.
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Table 1: Overview of small find number, context number and content of block at time of
lifting
Small Find
3061
3062
33731
33732
33733
33734
33735
33736
33737
33738
33743
33744
Context
92023
92023
92023
92023
92023
92023
92023
92023
92023
92023
92024
92024
Bone/ Antler
x
x
x
x
x
x
x
x
x
x
x
x
Wood
x
x
ASSESSMENT
Blocklifted bone, antler and wood was X-rayed by Angela Middleton and visually
examined together with Fay Worley (Zooarchaeologist) and where botanical material was
present in consultation with Gill Campbell (Archaeobotanist) and Zoe Hazell (Charcoal).
Generally speaking this material was damp and in a poor state of preservation. The
bone/antler is fragmented, the wood is degraded to such an extent that it is not always
recognisable as wood. The clay is extremely dense and adheres strongly to the
wood/bone/antler.
Some blocks had already started to dry out, most had developed mould in isolated
locations. The lifting process was not always ideal and some damage has occurred due to
unsuitable lifting material, such as flexible plastic lids.
During the visual assessment it became clear that X-radiography had limited value, due to
the lower density bone/ antler lying on top of dense clay. A zooarchaeological analysis
based on the X-radiographs alone was not possible. The bone/ antler had to be
excavated from the surrounding soil, in order to answer questions regarding:




animal species represented,
skeletal elements represented,
presence of evidence for processing (butchery marks, helical fractures, burning,
bone working)
possible presence of bone tools (particularly antler picks and cattle scapulae).
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Some blocks contained wood and it was to be ascertained whether this was worked or
natural.
It was necessary to trial the excavation and conservation strategy. Small find (SF33733)
was identified as showing least zooarchaeological potential and was chosen for the trial.
EXCAVATION AND CONSERVATION OF THE BONE/ ANTLER
Upon examination it became evident that the osseous material was very fragmented. If
left to dry, the material would further split, crack and delaminate, potentially further
diminishing its zooarchaeological potential. It was therefore decided to consolidate the
bone/ antler in the wet/damp condition using Primal WS24, an acrylic colloidal dispersion
in water (Horie 1987, 110). As the use of this consolidant will affect any C14 dating, an
untreated, air-dried sample of each small find was retained for future dating/analysis. It was
noticed that the outer bone cortex was lost in most cases. This surface potentially holds
valuable zooarchaeological information (such as butchery marks), so particular care had to
be paid when cleaning the remaining areas of cortical surface.
The following section describes the conservation work carried out on each small find.
SF33733
This small find was chosen to test the conservation method. The proposal was to remove
excess clay and then to consolidate a thin layer of clay onto the bone’s surface, which was
then to be removed by air abrasion. It was covered with clay almost all over and one
large crack was already visible (Figures 3–4). Excess clay was removed mechanically with a
wooden skewer. A small layer was left close to the bone’s surface. During the cleaning the
bone broke into two fragments along the existing crack. Both fragments were
consolidated using 20% (v/v) Primal WS24 in water, applied with a pipette. The fragments
were placed inside a box and the lid was loosely placed on top to allow for slow air
drying.
Both fragments still looked and felt damp after one day. The lid was therefore removed to
encourage air drying. After another day both fragments were dry. The smaller of the two
fragments was air-abraded to remove adhering soil. This technique worked fine for
thinning the layer of clay, but the clay close to the bone could not be removed without
causing too much damage to the bone’s surface (Figure 5). As a result this technique was
disregarded.
The adhering soil on the second slightly larger fragment was removed under magnification
with a scalpel (Figure 6). This was more successful and resulted in less damage to the soft
bone surface. After consolidation the bone’s identification is most likely to be a cattle ulna.
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Figure 3: SF33733 before cleaning, plan view
Figure 4: SF33733 before cleaning,
side view
Figure 5: SF33733 after cleaning and consolidation. Fragment on the left cleaned
mechanically with scalpel, fragment on right air-abraded.
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Figure 6: SF33733 after cleaning and consolidation. Reverse face to view seen in Figure 5
Fragment on the left cleaned mechanically with scalpel, fragment on right air-abraded.
SF33735
The bone surface appears crushed and has splintered into many little fragments (Figure 7).
In this case clay was removed by gently squirting tap water onto the surface and
dislodging it with a brush over a sieve. This worked well, especially in the areas that had a
well preserved bone surface. However, where a lot of crushing had occurred, small bone
splinters were flushed away. The bone was cleaned as much as possible on top and on
the side, leaving it on a little pedestal of soil. It was then consolidated from the top with
20% (v/v) Primal WS24 in water, applied by pipette. The pedestal of clay was wrapped in
cling film to prevent it from drying out (Figure 8). The bone was left open to air dry on
top. After two days the bone surface was sufficiently consolidated. The bone with the
adhering soil was then turned over and placed on a sand-filled bag. The clay was removed
and the cleaned surface was consolidated as described above. After another two days, the
bone was consolidated totally. It can now be handled and examined with care (Figures 9–
10). It was identified as a Bos radius.
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Fig 7: SF33735 before cleaning, plan view
Fig 8: SF33735 during cleaning, top is
consolidated, underlying clay is wrapped in
cling film
Figure 9: SF33735 after cleaning and
consolidation
Figure 10: SF33735 after cleaning and
consolidation
During the cleaning of the clay on the underside, another bone, a pig astragalus, was
found. This was cleaned and consolidated as described above.
SF3062
This small find consisted of several pieces, one of which was readily recognisable as a
tooth (Figure 11). All fragments were cleaned using tap water from a squirty bottle, a
brush and wooden skewer over a sieve.
One fragment was wood. The wood was very degraded and soft. Cleaning resulted in the
removal of wood fibres. After a discussion with G. Campbell it was decided that it was in
too poor a state of preservation to attempt species identification. This piece was allowed
to air dry and discarded.
The tooth and other two bone fragments were cleaned as described as above (SF 33735)
and consolidated using 20% Primal WS 24 (v/v) in water. The bone remained very
crumbly even after consolidation, and most could not be identified, although the tooth
was confirmed as cattle, and the surviving pieces appear to include cranial fragments
(Figure 12).
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Two ceramic fragments were found inside the soil. These were left to air dry.
Figure 11: SF3062 before cleaning, plan view
Figure 12: SF3062 after cleaning and consolidation
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SF33731
This small find was lifted in two separate blocks due to its size (parts 1of 2 and 2 of 2). It
was originally identified as an antler, possibly an antler pick (Figure 19).
Part 1 of 2 was very fragmented and several large cracks were visible (Figure 13). This
part had been stored on a flexible lid, which may have contributed to the frequency of
cracking. Compared to the block lifted bones, the antler seems to be much softer and
fragmented differently, (the bones delaminated and often broke up into very fine splinters,
whereas the antler broke into more ‘chunky’ pieces). Cohesion of the antler fragments
was mainly due to the water inside the cracks and the surrounding clay. Once the clay
was removed and water started to evaporate or more water was introduced during the
cleaning, parts of the antler fell away. Due to this fragmented nature, it is very unlikely that
these parts can be adhered again, and the research value of refitting such a fragmented
and degraded specimen was deemed low. One fragment (labelled A) was removed and
consolidated with 50% Primal (v/v) in water. Cleaning the surface took place using tap
water from a squirty bottle, a brush and wooden skewer. The clay was very sticky and did
not come off as easily as from the bones. Due to its condition, the antler could only be
cleaned on top. It was not consolidated and was left sitting on a pedestal of clay, allowing
the fragments to stay in their relative position (Figures 14–15).
Point where
antler joins to 2
of 2
Fragment A
Figure 13: SF33731 (1of2) before cleaning, plan view
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Figure 14: SF33731 (1of2) after cleaning
Figure 15: SF33731 (1of2) after cleaning, as Figure 14 rotated 180ºC
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Point where trez
would have sprung
B
Point where
antler joins
to 1 of 2
C
A
D
Figure 16: SF33731 (2 of 2) before cleaning
Figure 17: SF33731 (2 of 2) after cleaning
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Figure 18: SF33731 (2 of 2) showing probable wood remains, labelled D on Figure 16
Part 2 of 2 consisted of four main fragments, as shown below (Figure 16). All fragments
were cleaned with tap water and a soft brush over a sieve. Two fragments (labelled B and
D, see Figure 16) once cleaned, appeared to be degraded wood and were unrelated to
the antler. The wood fragments were retained in wet condition in cold storage alongside
the antler. Fragments A and C presented a fragmented surface and were in a very poor
condition. For this reason, they were not removed from the soil entirely, but left resting
on their block with only the uppermost surfaces exposed (Figure 17). This allowed the
fragments to stay in their relative positions.
The small find was confirmed as antler. Part 1 of 1 representing the base of the antler and
brow tine (Figure 19). It was not possible to be certain whether it had been shed,
although this was thought likely. Fragments A and C were identified as a continuation of
the beam from its connection with piece 1of 1 to beyond the trez tine. The trez was only
present as a stump, and it is not clear whether this had been removed in antiquity, as part
of pick manufacture, or had been lost through post-depositional damage.
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Figure 19: SF33731 Drawn record 1of 2 at top, 2of2 below. These fragments were
divided to enable block lifting
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SF33732
This small find was lifted on tin foil in several pieces (Figure 20). Cleaning was carried out
using tap water from a squirty bottle, a brush and wooden skewer over a sieve. On
discussion with G. Campbell it was concluded that the wood showed no signs of working
and was natural. It was retained damp in the cold room for wood species identification.
Overall, there was very little bone in this assemblage. Bone fragments were consolidated
using 20% Primal WS 24 (v/v) in water.
Wood
Wood
Wood on top,
bone
underneath
Mainly soil with
very few bone
fragments
Bone
Figure 20: SF33732 before cleaning
SF33734
This small find was lifted in a block that included a large stone upon which the bone
rested (Figure 21). Although held in position by the soil block, the object was in two main
pieces and several fragments around the area of the break (Figure 22). A wooden skewer
and soft brush were used to clean the object with tap water from a squirty bottle. The
surface was consolidated with 20% Primal WS24 (v/v) in water. Fragments were removed
and retained on a plan drawing of the bone so that they could be replaced later. The two
main fragments of the bone were then separated, and each turned over and excavated
from the soil block, both for ease of working and for the safety of the object. Some soil
was retained within the bone where it proved to be supporting the structure. The newlyexposed surface was then also consolidated with the 20% Primal solution and left to air
dry (Figures 23–24).
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Figure 21: SF33734 before cleaning and
consolidation
Figure 22: SF33734 during cleaning of the
upper surface
Figure 23: SF33734 after cleaning and
consolidation (note: fragments from
within break are not shown here)
Figure 24: SF33734 after cleaning and
consolidation (note: fragments from within
break are not shown here)
SF33736
This object was shown on X-radiographs to be very thin on top of the soil block (Figures
25–26). The upper surface was cleaned with tap water in a squirty bottle over a sieve,
with a soft brush, and then consolidated with 20% Primal WS24 (v/v) in water applied
with a pipette. On inspection this surface proved to be the interior rather than exterior
surface of the bone and of no zooarchaeological potential for recovery of information
regarding carcass processing. It was considered too fragile to turn the soil block over in
this condition, so the surface was further consolidated by applying small strips of Japanese
tissue along lines of weakness (Figure 27). Once dried, the block was turned over and the
exterior face of the bone exposed in the same way, with the object resting on a cushion
of bubble wrap. This was then consolidated with 20% Primal WS24 (v/v) in water. This
surface showed a clear ancient break at one end, possibly a chop mark, which had been
filled with sediment, suggesting that this was butchered and was very unlikely to have
been used as a scapula shovel (Figures 28–29).
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Figure 25: SF33736 before cleaning and
consolidation
Figure 26: SF33736 before cleaning and
consolidation
Figure 27: SF33736 during consolidation
with Japanese tissue on upper surface
Figure 28: SF33736 after cleaning and
consolidation of the other surface; ancient
break indicated by arrow
Figure 29: SF33736 after cleaning and consolidation, showing chop mark
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SF33737
This small find was initially identified as a collection of bones, comprising a large mammal
longbone, indeterminate large mammal-sized bone and a Bos, possibly aurochs, scapula.
There appeared to be at least three bones in the block but the soil obscured any further
detail and the central area of the block was badly cracked and fragmented (Figure 30).
The use of a flexible lid to lift this assemblage may have contributed to cracks. Each
apparent individual bone or fragment was numbered as shown in Figure 30, and cleaning
of the uppermost surfaces carried out with tap water and a soft brush. The block was
planned at a 1:1 scale on melinex (Figure 31).
B2
A
B1
C1
C2
C3
Figure 30: SF33737 before cleaning
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Figure 31: Drawing of SF33737 after removal of bone ‘A’, plan view
The bone marked ‘A’ was part of a mammal long bone that had been partially squashed
during excavation. This was removed first, cleaned as far as possible and consolidated
using a 50% solution of Primal WS24 (v/v). After cleaning the upper surfaces of the
remaining bones, the block was separated along the large transverse crack in the central
area for ease of working. Fragments from this area were consolidated with 20% Primal
solution and retained on the plan to aid in any re-fitting later (Figures 34–36).
Fragment C1 was excavated next, and could be easily separated from the block
containing B2, as there was no contact between these fragments. C1 was cleaned and
consolidated by applying 20% Primal WS24 (v/v) in water with a pipette and soft brush
(Figures 32–33).
Figure 32: SF33737 fragment C1 after
cleaning and consolidation
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Figure 33: SF33737 fragment C1 after
cleaning and consolidation
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Fragment B2, part of the scapula, could then be turned over and rested on a bag of
linseeds to support the cracked exposed surface. Soil was cleaned away using a wooden
skewer and brush with tap water from a squirty bottle. Several detached fragments of
bone from the soil block beneath the scapula were retained; these could not easily be
identified due to their poor condition. As much of the soil as was possible was removed,
but the edges of this fragment of scapula were very thin and fragile, so it was not
appropriate to entirely clean the surface. This surface was consolidated with 50% Primal
WS24 (v/v) in water, but on air drying the cracks opened and it was apparent that the
bone was in at least ten smaller fragments, although still in the correct positions (Figure
37). While these fragments are unlikely to be sufficiently robust to be refitted in future,
the freshly consolidated bone revealed that the blade was largely complete and the
scapula spine not modified, suggesting that it was unlikely to have been used as a shovel.
Fragments B1 and C2 were also cleaned by the same process, but could not be separated
from each other as this would have resulted in severe damage to at least one of the
bones. A protruding piece of the scapula (B1) was reinforced with Japanese tissue to
prevent its breaking away. It retained its form enough to allow measurement of the
scapula neck following standard conventions (von den Driesch 1976) and assist species
identification. C2 was shown to be a partial Bos pelvis (Figure 38), but could not easily be
refitted with fragment C1. The exposed surfaces of B1 and C2 were again consolidated
with 20% Primal WS24 (v/v) in water and allowed to air dry slowly.
Fragment C3 was also cleaned and consolidated in the same manner, but was found to be
very thin in comparison. It is probably part of the pelvic bone and may re-join to fragment
B1 (Figure 39).
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Figure 34: SF33737 during cleaning and
before separation of fragments
Figure 35: SF33737 after removal of fragment
A, showing scapula surface
Figure 36: SF33737 after removal of
fragment A
Figure 37: SF33737 showing the exposed
underside and blade of scapula fragment B2
Figure 38: SF33737 showing pelvic fragment
C2 after cleaning and consolidation, still
attached to B1
Figure 39: SF33737 fragment C3 after
cleaning and consolidation
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Figure 40: SF33737 Drawn record. Clockwise from top left: proximal scapula, lateral view;
relative positions of fragments; pelvis lateral view, with distal scapula seen behind; scapula
glenoid cavity (distal view) seen underlying pelvis; cross section of preceding distal view;
distal scapula, medial view, with pelvis seen behind.
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SF33738
Initially it was unclear whether this piece was an antler tine or part of a long bone (Figure
41). Cleaning was carried out using tap water from a squirty bottle, a brush and wooden
skewer (Figure 42) over a sieve. The top part was consolidated with 20% Primal WS24
(v/v) in water, applied by pipette. The pedestal of clay was wrapped in cling film to
prevent uncontrolled drying. After drying the piece was turned over and the process
repeated for the underside. The find proved to be a medium mammal sized long bone,
with surviving evidence for processing (helical fractures) (Figures 43–44).
Figure 41: SF33738 before cleaning, plan view
Figure 42: SF33738 during cleaning
Figure 43: SF33738 after cleaning and
consolidation
Figure 44: SF33738 after cleaning and
consolidation
SF33743
The initial assessment suggested that this small find was possibly antler (Figure 45),
however the object proved to be a Bos distal radius (partial – may relate to partial radius
SF33735), with helical fracturing suggestive of processing. The object was cleaned with tap
water from a squirty bottle, using a brush and wooden skewer to remove the soil. A large
crack was visible across the width of the object (Figure 46) and the surface proved to be
inner cortical bone, with no external bone surface surviving. In order to turn the block
over without damaging the bone, the exposed surface was consolidated using Japanese
tissue along lines of weakness (Figure 47), and a 20% solution of Primal WS24 (v/v) in
water. Once dried, the block was turned over on a cushion of foam and cling film, and
excavated to expose the other surface. This surface was then consolidated with 20%
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Primal solution, but on drying further cracking of the surface occurred – these areas were
then consolidated with 50% Primal WS24 (v/v) in water, which was more successful
(Figure 48), however the bone remains particularly fragile.
Figure 45: SF33743 before cleaning, plan view Figure 46: SF33743 during cleaning,
showing crack
Figure 47: SF33743 during consolidation with
Japanese tissue
Figure 48: SF33743 after cleaning and
consolidation
An untreated air-dried bone sample has been retained.
SF33744
The initial assessment identified this as large mammal bone and wood. Both bone and
wood displayed some large cracks (Figure 49). Cleaning was carried out using tap water
from a squirty bottle, a brush and wooden skewer. The wood could not be cleaned
successfully. It is much softer than the surrounding clay and continuous cleaning with
water and brush resulted in a loss of wood fibres. On discussion with G. Campbell it was
concluded that the wood appeared to be natural, rather than an artefact, and that it was
in a very poor state of preservation and did not merit conservation or retention (Figure
50). The part containing the wood was removed from the bone, left to air dry and
discarded. In order to proceed with work on the bone, it had to be removed from the
seed tray it was collected in. The clay was separated from the seed tray with a string of
fish wire, which was pulled through the clay as close as possible to the base of the seed
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Figure 49: SF33744 before cleaning, plan
view
Figure 50: SF33744 bone cleaned on top,
wood partially cleaned
Figure 51: SF33744 bone lifted out of tray
Figure 52: SF33744 part of bone fallen over
Figure 53: SF33744 bone after drying
Figure 54: SF33744 bone after drying
tray. The whole clay pedestal, still containing the bone, was then lifted out of the seed tray
using wooden cooking spatulas and placed on a flat tray (Figure 51). Following this
process, one end of the bone fell over, resulting in further disassociation of bone
fragments (Figure 52). Parts of this could be placed back into position. More clay was
removed from the bone with water and brush. The upper surface was consolidated with
20% Primal WS24 (v/v) in water, applied by pipette. The pedestal of clay was wrapped in
cling film to prevent it from uncontrolled drying. A change in work programme caused a
delay in continuing work on this bone. This resulted in the complete drying of the
underlying clay and the development of large cracks of the bone. The bone is very fragile.
It can not be removed from the clay and a decision was taken to leave on the clay
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pedestal, rather than risk further damage (Figures 53–54). It has been identified as a large
mammal (probable Bos) tibia.
SF3061
This find was very small and fragmented (Figure 55). It was cleaned on the top surface,
mechanical with a wooden skewer. An examination by Fay Worley confirmed that this
piece was probably antler. However, there was too little of it remaining and in too poor a
state of preservation to positively identify it and to merit conservation (Figures 56–57).
This piece was recorded, left to air dry and discarded.
Figure 55 : SF3061 before cleaning
Figure 56: SF3061 after cleaning
Figure 57: SF3061 after cleaning, view inside the break
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CONCLUSION AND RECOMMENDATIONS
The work on the block lifted bone and antler from Marden Henge was informative both
from a zooarchaeological and conservation method point of view. It revealed useful
zooarchaeological information with regards to animal species, element and age-at-death
and depositional pathway (many were processed bones, rather than partial/whole fleshed
carcass) (Worley forthcoming). In terms of conservation, the team were able to develop a
successful conservation methodology: cohesion of the fragmented bone and antler was
mainly due to surrounding clay and water within the cracks. These cracks opened up once
the clay was removed or too much water was used for the cleaning. A slight wetting of
the clay to make it softer and removal of clay by wooden skewer seemed to work better
than flushing the clay away. This method worked well and in most cases it resulted in
stable bone, which can be handled and examined with care. In most cases the original
surface of the bone had already been lost. The first method trialled, involving partial
removal of clay followed by consolidation and air-abrasion was disregarded, as it caused
too much damage to the bone surface.
If Marden Henge should be investigated again in the future we can be better prepared for
the conditions on site and the condition of the osseous material. For lifting, flexible
materials such as seed trays, lids or Corex® should be avoided. Not only did these
materials allow some movement and therefore adversely affected the survival of fragile
osseous material, but their internal structure also shows on the X-radiograph, making their
interpretation more complicated. The use of Perspex sheet or aluminium with a
separation layer of cling film could be explored. Freeze lifting may be another option.
REFERENCES
Horie, C V 1987 Materials for Conservation. Organic consolidants, adhesives and coatings.
London: Butterworth
Leary, J 2010 Marden Henge Excavations, Wiltshire. Stage 2. Project 5219. Project design
for Stage 2. Internal English Heritage project design
von den Driesch, A 1976 A Guide to the Measurement of Animal Bones from
Archaeological Sites. Peabody Museum Bulletin 1. Harvard University: Peabody Museum
of Archaeology and Ethnology
Worley, F forthcoming Interim Report on the Animal Bone Excavated in 2010.
Portsmouth: English Heritage
© ENGLISH HERITAGE
25
25 - 2013
ENGLISH HERITAGE RESEARCH AND THE HISTORIC ENVIRONMENT
English Heritage undertakes and commissions research into the historic
environment, and the issues that affect its condition and survival, in order to
provide the understanding necessary for informed policy and decision making, for
the protection and sustainable management of the resource, and to promote the
widest access, appreciation and enjoyment of our heritage. Much of this work is
conceived and implemented in the context of the National Heritage Protection
Plan. For more information on the NHPP please go to http://www.english-heritage.
org.uk/professional/protection/national-heritage-protection-plan/.
The Heritage Protection Department provides English Heritage with this capacity
in the fields of building history, archaeology, archaeological science, imaging
and visualisation, landscape history, and remote sensing. It brings together four
teams with complementary investigative, analytical and technical skills to provide
integrated applied research expertise across the range of the historic environment.
These are:
*Intervention and Analysis (including Archaeology Projects, Archives,
Environmental Studies, Archaeological Conservation and Technology, and Scientific Dating)
*Assessment (including Archaeological and Architectural Investigation, the Blue Plaques Team and the Survey of London)
*Imaging and Visualisation (including Technical Survey, Graphics
and Photography)
*Remote Sensing (including Mapping, Photogrammetry and Geophysics)
The Heritage Protection Department undertakes a wide range of investigative
and analytical projects, and provides quality assurance and management support
for externally-commissioned research. We aim for innovative work of the highest
quality which will set agendas and standards for the historic environment sector.
In support of this, and to build capacity and promote best practice in the sector,
we also publish guidance and provide advice and training. We support community
engagement and build this in to our projects and programmes wherever possible.
We make the results of our work available through the Research Report Series,
and through journal publications and monographs. Our newsletter Research News,
which appears twice a year, aims to keep our partners within and outside English
Heritage up-to-date with our projects and activities.
A full list of Research Reports, with abstracts and information on how to obtain
copies, may be found on www.english-heritage.org.uk/researchreports
For further information visit www.english-heritage.org.uk
ISSN 2046-9799 (Print)
ISSN 2046-9802 (Online)