Anglo-Saxon CSI: Sittingbourne


Conserved objects
September 12, 2009, 9:50 pm
Filed under: Conservation

CONSERVED OBJECTS

This page aims to show you what we have been working on in the lab.  The page will be updated as and when we have worked on something interesting.  Be sure to check back regularly.

VOLUNTEER OBJECTS

Volunteer Sylvia has written a short piece on a copper alloy object she has been working on.

“Thinking back over the past 3 months probably the best thing I have worked on was a copper ring – not much to get excited about there you might think but this ring was about an inch or more in diameter, it brought to mind the kind of ‘woggle’ Boy Scouts used to keep their scarves in place but this was shiny like malachite, the precious mineral, and much the same colour too.  It was thick with Swale mud and the only way to clean it was with a cotton bud soaked in IMS.  Through the microscope the surface was cracked and pitted, a small fragment broke away and revealed charcoal coloured copper beneath.  At first I thought it was enamel but after working for a while on it I realised enamel would not be so thin a covering as this;  apparently the original description of ‘copper ring’ was just right.  I could not wait to get back to work the following week and finish off this small ‘gem’ of a piece, then the imagination starts to race – who used this, and what for?  Was it an ornament or a piece of everyday equipment? Belonging to a man or a woman?  We may never know, so back to work on the next piece….”

DO YOU KNOW WHAT THIS IS?

This is an uncommon and unidentified object is made from copper alloy.  It is silver plated on one side and has evidence of leather and wood on the reverse.  There are several holes in the object and the diameter is approximately 7cm.

Front of mystery object showing silver plating

Front of 'mystery' object showing silver plating

Reverse of 'mystery' object showing leather and wood evidence

It comes from grave 115, which is a male grave and one of the richer ones with a sword present.  According to the grave plan it was found on the left hand side of the man, probably close to his hand although we can’t be sure as no bones have survived in the burial.

Grave 115 plan showing whereabouts of the "mystery object" (Image copyright Canterbury Archaeological Trust)

JEWELLERY

In a number of the graves the archaeologists found brooches.  These have already been cleaned and conserved and are in a safe place away from the CSI: exhibition.  These brooches are gold and copper alloy and have very intricate and skilled decoration present.  Garnet stones have been inlaid for added decoration and colour.  These stones are probably of eastern origin, showing the links that the Anglo-Saxon kingdom of Kent had around the world.  One of the brooches, with Frankish style influences, has been attributed to being made in nearby Faversham.

Part cleaned saucer brooch with inlaid garnet stones

Plated disc brooch attributed to being made in Faversham

BUCKLES

Buckles are a common find in Anglo-Saxon burials and are commonly associated with male graves.  Some are decorative copper alloy and gold and others may be iron with decorative studs/rivets.  Archaeologists believe that the people were buried clothed opposed to the objects being added as tokens to the persons life.  A decorative gold plated copper alloy buckle was discovered at The Meads and has already been conserved.  The volunteers have been working on iron buckles and have found decorative copper alloy and silver studs, along with evidence of mineral preserved leather against the surface of the iron.

Copper alloy buckle discovered in one of the graves

Volunteer Wendy is currently working on a buckle with decorative copper alloy rivets and has produced an ‘interesting’ illustration of her discoveries.

Illustration of iron buckle currently being worked on in the lab

SWORDS

There were 11 swords discovered when excavating the site.  Most of these have either been fully conserved or partially conserved and have revealed a lot of interesting and valuable information.  Some of these have even been taken to Switzerland for accelerated neutron tomography analysis, which is a non-destructive form of research aiming to look at the evidence for pattern welding on the swords.  We should be getting some results back soon!

Below are some blog reports that have been written by student conservators who worked on these objects over the summer.

Anglo Saxon Sword – TMS II EX08 Grave 83 (237)

Before conservation treatment

Measures : 64 x 14 cm

The sword and the dagger was block-lifted together with cling film and plaster bandages.

It was covered with soil and stones from the grave (Fig. 1).  We have to record what we see on the surface as it was close to the decaying body.

Fig. 1: The sword (green arrow) and dagger (blue arrow) covered with the excavation soil

The digital x-ray image (fig. 2) show the sword and the dagger in a badly corrosion state: the sword is fragmented and the metal is mineralized.

Evidence of stripes are not so obvious on it, compared to other swords from the same excavation.  However, large black areas are visible on the sword (handle, mid) and on the blade of the dagger.  These could be the remains of mineralised organic materials or they might also be from corrosion products under the soil.  A sort of spiral at the edge of the sword taken maybe in a stripe is visible on the x-rays similar to the sword frome grave 115 (397).  Besides, we can also see crossing lines on this sword which must be an evidence of the pattern welding.  A grey area on the x-rays located between the sword and the dagger might possibly be a physical connection between the two objects (maybe mineralised organic materials ?) . On top of that a metal (?) object is located near this area on the handle of the dagger.

Fig. 2: Digital x-ray image showing the corroded metal, one stripe on the sword (black lines) with metal objects (red circles).

During the treatment

The first stage consisted with removal of the excavation soil using a microscope (magnification x10) find the last surface of the sword.  We used a scalpel, brush and air abrasion for the mechanical cleaning and IMS (industrial methylated spirits) with water (50/50) to soften the soil.

This sword is particularly interesting because of the remains of  mineralised wood where the direction of the grain differs (see below) and it is the only grave with this association of sword and dagger together.  It was decided that we should analyse further by using neutron tomography analysis, located in Switzerland.  Before turning and cleaning the other surface near the plaster bandages, we used CDD (cyclododecan) wax (fig.17) to protect the fragile elements between the sword and the dagger; the fragmented surface of the wooden sheath and other parts were consolidated with Paraloid B72 (acrylic resin) with 30% of acetone.

Over the course of this treatment, some elements were discovered that may be of interest to the archaeologist; they are listed below in the table.

Further examination and analysis with a microscope is required to:

  • determine the type of organic and metal materials used and the techniquess required
  • help for a reconstruction of the location of the various items on the unit and their function,  to understand better the relationship with them and the others elements in this grave

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