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We will take questions on the website or via Twitter – using the hashtag #hoardchat.

This boss could have been used to secure sword hilt plates together as seen in a different hoard object, K563 (Figure 2).

Figure 2. K563, a pair of hilt plates riveted together. See circled area on right side for similar boss with pin (though this boss is has sustained greater damage than K1536).

When performing a condition assessment of the boss it was noted that there was unidentified black material inside the boss around the base of the pin (Figure 3).

Figure 3. Black material inside K1536. Magnification 50x.

Because this object is going out on loan, which will involve additional handling for packing, transportation, and condition checking on installation and de-installation, there is a potential risk that this delicate residue may become detached. As such, the decision was taken to remove the larger, more vulnerable portion of the residue to ensure its safety and to allow scientists to analyse it. Some of the residue remains inside the boss, but now we can move forward with analysis while the object is away on loan.

The standard procedure for dealing with unidentified residues is to photograph and document them and to set aside the object for analysis, which could take it out of circulation temporarily while the work is carried out. However, this is not always practical or possible, in which case an alternative approach is taken: sampling the residue.

In conjunction with the British Museum, the hoard conservation team has created a set of sampling procedures that allow the team to gather samples for analysis while allowing the object to remain available for display or research. The areas with residue are considered carefully, then, working under magnification, a sample is removed. The sample is stored in a small glass tube marked with the accession number (Figure 4) and packed securely into a storage box.

Figure 4. Sample tube containing the residue from K1536.

Information about the sample is then entered into a spreadsheet that lists all samples taken to date. The sampling procedure and location are noted on the object’s condition report, and photographs of the object before and after sampling are taken and annotated to point out the location from which the sample was taken (Figures 5 and 6).

Figures 5 and 6. K1536 before (left) and after (right) removal of the sample. The sampled area is marked with an arrow.

To get a better look at the residue after removal, I examined it using our 3D digital microscope (Figure 7).

Figure 7. Examining the residue using a Keyence VHX-1000 3D digital microscope. Magnifying range: 20-200x.

The material has a somewhat rough, glossy, resinous appearance with an apparently light-coloured core (see Figures 8 and 9).

Figures 8 and 9. K1536 residue. Magnification 50-100x.

At this point we do not know what the residue is made of or why it is there. It might be some kind of filler or adhesive to help support the gold pin, which is soldered to the inside surface of the boss. Determining the composition of the residue might help us understand its purpose.

We have a partnership with the British Museum for support with conservation and scientific research, allowing us to draw on the BM scientists’ and conservators’ valuable expertise and experience in analysing and treating similar archaeological material. The BM also has analytical equipment not available at Birmingham Museum such as x-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, and gas chromatography/mass spectroscopy (GC/MS). It is hoped that analysis of residues such as the one found in K1536 may further our understanding of the Anglo-Saxon craftsman’s materials and techniques.

In March the British Museum’s metals conservation department will be hosting the hoard conservation team. The hoard team will get an insight into the different types of analytical processes that are applicable to different objects and work on a one-to-one basis with the metals conservators who have worked on such projects as Sutton Hoo. News about this visit will be posted, so check back again soon.

Cymbeline Storey

Staffordshire Hoard Conservator

Birmingham Museum & Art Gallery

The Mystery Object: K130, K1055 and K545

Thanks, everyone, for your suggestions as to what the ‘mystery object’ might be.  Sorry it has taken a while to get around to replying to you, but there was a mountain of emails and other work waiting for me when I got back from Washington. Anyway, let me finally try and comment on some of the ideas that have been put forward:

It’s a lid of some kind:

This seems a possibility. The open end of K130 certainly has rivet holes around the edge, showing it was fixed to something else. This could well have been some kind of stopper, possibly to fit into the mouth of a vessel of some kind. One favourite suggestion is that it might have been the stopper for a drinking horn. This would be the first one of these known, but then the hoard is springing lots of surprises on us. The vessel would have to be small though; we estimate the original diameter of the bottom of K130 was about 7.0-7.5 centimetres (3 inches).

Specifically, it’s the lid of a thurible or censer:

The big problem with this suggestion is that there are no holes in K130, which would actually be the cover over the burning incense. I can’t think of a censer cover that doesn’t have holes to let the scented smoke out. There is also no sign of any smoke residue on the underside of K130. (For the same reasons I don’t think it is likely that this the cover of an oil lamp.)

It’s a drawer or cabinet handle:

I can see where the idea comes from, and I agree the shape is very reminiscent of this, but I don’t think there is any evidence that the Saxons had such elaborate furniture. I also don’t think the assembled pieces would have been strong enough to last very long in use as a drawer handle.

It’s a mount from the top of a helmet:

This is an interesting suggestion. Nothing similar has been found so far, but helmets of this period are exceptionally rare, so this isn’t really a major problem. The one thing that is clear is that the assemblage could not have supported a plume or animal figure or feathers: it ends in a decorated glass gem (on the tip of K545) and that is it. Of course the glass gem would then be on the very top of the helmet and out of sight when it was being worn, which doesn’t seem the best use for one of the really striking decorative elements. I also wonder whether the rivet holes in the lower edge of K130 really look strong enough for the job. We need to talk to one of  our friends who makes reproduction helmets and see what he makes of this idea – watch this space!

It’s a sword hilt:

I don’t think this assemblage would be anywhere near strong enough to work as a sword hilt. Also, there is nowhere for the tang of the sword blade to fit, so we would have to imagine all these three bits perched on top of the hilt, which would make it rather unwieldy. Finally, this would be a unique shape for a sword hilt. Of course, this isn’t a cast-iron reason to reject the idea since the hoard is giving us a lot of things we’ve never seen before, but we do have pieces from over ninety ‘normal’ hilts already.

It’s a candlestick:

The big problem with this idea is that the open end of K130 was rivetted to something else, so it presumably wasn’t open and thus couldn’t have held a candle. You could not have put a candle in the other end because K545 ends in a mounted glass gem.

It’s part of a spindle:

If you assume this is part of a spindle, then presumably you have to see the shaft of the spindle as being rivetted into the open end of K130, but the opening is about 7.0-7.5 centimetres (3 inches) in diameter, which would be absolutely huge for a spindle shaft.

It’s a mirror:

I presume the idea is that the inner surface of the open end of K130 was the reflective surface that formed the mirror. Two big problems here. First, something was rivetted to K130 at that end so the inner surface probably wasn’t visible. Second, if it was visible, there was a lot of ‘stuff’ going on inside that concave area of K130; for example, this is where the silver connecting piece that attached to K1055 was anchored – and that’s not really what you want in the middle of a mirror. You might be able to argue, though, that some kind of reflective surface was fixed to K130, meaning our mystery object formed the handle. Again, this would be unique, but ….

It’s a stamp, to seal things:

A nice idea, but the glass gem at one end (on K545) is smooth, so that wouldn’t work as a seal matrix. At the other end, the open end of K130 is about 7.0-7.5 centimetres (3 inches) in diameter, so whatever was rivetted to it would really have been much too big for a seal matrix.

It’s the top of a parasol:

It does look very ‘top-like’, but again the big problem with this this suggestion is the diameter of the open end of K130, which is where the shaft of the parasol would presumably have been fixed if this group of objects formed the finial at the top. The  opening is about 7.0-7.5 centimetres (3 inches) in diameter, which strikes me as way to chunky for the shaft of a parasol.

It’s the decorative tip of a shield boss:

This was my initial idea when I first saw the piece reassembled, but this was really because it looks a bit like the tips of some Anglo-Saxon shield bosses. If it is from a shield, this would have to be a very elaborate example, mainly intended for show, although if this assemblage was rivetted to the tip of an iron boss, the shield could still function perfectly well. It is only fair to say that numbers of my archaeological colleagues don’t believe this idea! When it comes back from Washington we will need to look very carefully for any evidence as to what sort of material K130 might have been rivetted to.

It’s the upper part of a shishas (or hookah):

The real killer for this idea is that there is no hole through which the smoke could be drawn. Also, of course, the Anglo-Saxons didn’t have tobacco, nor am I aware that they smoked anything else. (If anyone has any evidence that they did, I would be fascinated to hear it.)

It’s the end of something that had to be rolled:

This is another idea that has been suggested here at the museum. One thought was that it might have been the terminal to a rod that held a scroll of some kind.. (K130 was damaged when the original object was disassembled; originally it was circular and either flat or slightly domed (like a saucer). I suppose the scroll idea runs up against the same problem as some of the other suggestions – the open end of K130 suggests that the rod that the scroll was rolled around must have been something like 7.0-7.5 centimetres (3 inches) in diameter, which again seems really excessive.

It’s a spice grinder:

This one can’t be correct, I’m afraid, as the pieces were rigidly fastened together – no movement, no grinding!

It’s the top of a staff of office, sceptre or a whetstone:

Again, these are ideas that we had thought of here, but they all seem to fall foul of the quite large size of whatever was fixed to the open end of K130 – a diameter of 7.0-7.5 centimetres (3 inches) just seems to big for a handle for any of these objects.

It’s a bit mount:

This is another interesting idea. I am not well enough up on horse harness to assess this suggestion myself, so could anyone let us know how exactly this would work. My immediate question is whether the assemblage would be strong eough for this kind of use. It doesn’t appear to have been particularly robust. One archaeological colleague suggested that it might be a mount from a saddle, but again I wonder if this would have put too much strain on it.

It’s a reworked brooch:

I can see what might make someone suggest this, but there are no signs that any of the pieces have ever had any form of pin fitting attached. The idea that the hoard is – or includes – loot is quite feasible. This is going to be one of the areas that will have to be very carefully assessed over next few years, as we prepare the hoard for publication. Given the activity of the successive Mercian kings, we could be dealing with material from East Anglia, Kent and/or Northumbria, as well as from Mercia itself.

I hope that people will find these musings of interest. Of course everything I have said could turn out to be quite wrong – but that is half the fun of the hoard!

Please do keep sending us your ideas – we really do treat them all seriously as they all stop and make you think. Don’t worry if we turn most of them down, remember that we have the advantage of being able to handle the object and you don’t. We know that you are having to come up with ideas just based on the photographs.

Someone asked about the emblem that we are using as the Staffordshire Hoard logo. This is actually a piece of animal interlace design, of the kind that crops up on lots of objects in the hoard. (Even much of the filigree decoration on the pommel caps is a degenerated animal interlace; if you look carefully you can sometimes make out a slight lump or thickening that is what is left of an animal’s head.) The design that forms our logo is actually made up of what I call two ‘gripping monopedes’- each animal has basically been reduced to an elongated jaw that bites the torso of the other animal. You will see an eye at the back of the head, behind the jaw. Sticking out from the back of the body is a single leg (hence ‘monopede’) which ends in a three-toed foot. Presumably these patterns had some specific meaning for the Anglo-Saxon craftsmen who produced them, but we do not know what this may have been. I do like to think, though, that they also reflect some sense of fun and wonder as well.

Dr David Symons, curator at BMAG, Research Advisory Panel.

Standing in for Dave as curator I joined Exhibitions Manager Andy Horn and designer Simon Meddings in co-ordinating the move.  Stepping into Dave’s shoes was made easier as he and Andy had provided a large file of plans for the new display.

None of this would happen without the technical team, who arrived hotfoot from the installation of the beautiful  ‘Lost in Lace’ exhibition to work on the gallery.  The techs swiftly transformed the space – re-painting Gallery 12, moving old displays of Peruvian pottery into storage, mounting labels and bringing in cases from Gallery 16.

New panels explore key themes in the story of the hoard.

Gary wields a drill

Kate marking up

If you have ever wanted to know what happens in a museum at night, here we are with the Conservation team installing the gold hoard in the cases!

Deborah M and Gemma make it look easy

‘Left a bit!’ Magnification and lighting help even tiny garnets to shine

Hands on from start to finish! Final touches from Andy and Simon.

The New Gallery

More than a hundred Staffordshire Hoard objects can be seen in Gallery 12.  The display also highlights the developing story of the hoard with a new panel explaining the important work being done in the Conservation Studio.

A film clip from the National Geographic introduces the discovery and you can touch and feel Anglo-Saxon helmet mail or test the weight of an Anglo-Saxon sword and seax made by Paul Binns.

Replica Anglo-Saxon helmet

This is a fantastic opportunity to try out new touch-screen interactives, developed with Stoke Museum and our Mercian Trail partners for the summer exhibition.  These contain added information on major finds, such as the cross and the eagle mount.

Hoard interactives

As the British Museum curatorial placement I will be working with Dave and Andy for the next year on plans for a permanent Staffordshire Hoard gallery.

If you would like to help us input into the process please try out Gallery 12 and let us know what you enjoyed or what you would like to see more of here.

Morn Capper, British Museum Future Curator at Birmingham Museums and Art Gallery.

Image 1. K453, front.

Description

K453 is one of the larger pieces of the Staffordshire Hoard. This has been described as a silver gilt plate with rows of zoomorphic decoration. It has been called a cheek piece, because it strongly resembles the sides of a warrior’s helmet, but this has not been confirmed, as some argue that this object appears to be too small to serve that purpose. The research teams will be investigating this object further in the coming year.

Image 2. K453, side.

This object was likely cast and chased, it is approximately 100mm long, 80 mm wide and 19 mm deep, and weights almost 84 grams.

When an object made of silver has a layer of gold applied to its surface, it is called silver gilt. As can be observed from image 4, two layers of metal, one of silver and one of gold, can be seen on this object.

Conservation

The conservation of this object was limited to the removal of surface soil, in order to reveal the dense and interesting decoration. The darkening produced by the silver tarnish was left in situ, as was a patch of green corrosion product which may suggest the contact of K453 with a copper object during its burial. The back of the object (image 3) features patches of discolouration that may indicate contact or association with another material, possibly organic, that has left a dark stain on the gold surface. Note that the minimal extent of cleaning in this part of the object, as on the rest of it, is aimed at retaining as much material evidence as possible.

Image 3. K453, back.

Condition and first associations

Image 4 also shows the irregular, torn surface produced by the forceful removal of a component from that area.

Image 4. Silver gilt. Image taken with the Keyance 3D microscope, showing a cross section of the silver core of the object, to which a layer of gold was applied.

The overall shot of the object (image 1) shows that there are two gaps on its top edge. Conservators, having the opportunity to closely observe the objects they work on, can really get to know their features; that is why, while sorting trough several Hoard boxes during a grouping session, the four tabs in image 5 seemed to have much in common with K453.

Image 5. The tabs: discovered during a grouping session, were unidentified at first; my knowledge of K 453 prompted me to make a connection between them and the silver gilt plate.

Image 6. Tab K1507 matching the break on the edge of K453.

The tabs are made of silver, but they bear visible traces of gilt at their lower extremity (Image 7); their weight, thickness, state of preservation and fractured edges prompted me to match them against the gaps on the plate (Image 6) – two out of the four tabs match those gaps, taking into consideration the metal distortion suffered by the edges, which no longer allows for a ‘perfect’ fit.

Image 7. Magnified image of a tab, showing its torn end, an area of gilding and its silver grey main body. The cut marks on the edge suggest that a sharp object or blade was used to aid the dismantling of the piece, perhaps by creating a weak point in the area to be then bent and torn.

Further discoveries made during conservation

It also occurred to me during the cleaning that there were a series of short, vertical, equidistant marks along the top border: why were they there? What caused them? A possible answer is that they were caused by the ribbed wire gold objects in image 9, which were, up to that point called “eyebrows”, because of their similarity to such features on a face or potentially, an Anglo-Saxon helmet. They have now been renamed ‘fittings’. A discussion among experts, who observed a set of two oblong slots in the centre of these gold fittings, concluded that one of these must have fitted on top of the plate, with the tabs, in their original position, inserted though the slots, to form the grouping in image 9. The marks that the ribbed wire must have left on the plate (image 8 ) while rubbing against it during use provided further support for the match.

Image 8. Top edge – some of the vertical marks on the surface.

Image 9. The ribbed wire objects feature two slots each in the middle; the one on the left fits onto the edge of the plate, with the slots aligning with the breakages and the tabs.

Evidence of a second plate

Until a few weeks ago we had a first, exciting grouping, and the suggestion of a second one in the extra pair of tabs and the second fitting. Further evidence to the existence of a second plate came when its broken off side was discovered. It was conserved by one of our interns, who probably had little idea of what it was at the time. It was only while I was checking the pictures of some of the finished objects that I recognised that shape and decoration as being practically identical to that of K453. You can easily notice the similarity while comparing the object in image 10 and the side shot of K453 in image 2.

Image 10. A fresh addition: the torn off side of a second silver gilt plate: note the niello and intertwining snakes decoration, as in K453

Image 11. The side (K97) and tabs of a second plate which must have looked very similar to K453.

Many questions

This obviously raises the question: where is the rest of the second silver gilt plate? Images 12 and 13 show a severe case of the gilding layer breaking and delaminating from the back of K97, suggesting that it is possible that the gold may, to some extent, have separated from the silver underneath: Could some of the many fragments of what have so far been defined as sheet metal actually be detached and fragmented gilding? How did the destruction of K97 occur? Was it deliberate? And if so, why entirely rip apart one plate and leave the other relatively untouched? Why putting so much effort into breaking off those thick tabs? Is the answer to the question to be found on the value of gold and silver at the time?

Examination has suggested that the main body of the plate in its original state probably looked like solid gold,  as the gilding on it is quite thick. The tabs, on the other hand, although bearing thin smudges of gold and being now darkened by tarnish, are likely to have looked quite silvery: was there a chance that without the tabs the plate could have passed for solid gold and sold at a higher price? Part of these questions will be answered by further examination and analysis, such as a closer observation of the sheet metal fragments,and discussions and interactions with the research teams.

Image 12. The back of K97, with the broken gilding lifting and flaking off the silver underneath.

Image 13. Detail of the broken, lifting gilding, (Mag. X20)

It’s in the USA now!

The first plate, with its two tabs and the two ribbed wire objects are currently on exhibition at the National Geographic Museum in Washington DC, together with many more of the Hoard’s star pieces.

Deborah L Magnoler, Conservator, Staffordshire Hoard Conservation Team, Birmingham Museums and Art Gallery.

Mystery Object (K545, K1055 and K130)

Three pieces of the Hoard have been identified as belonging to one object, but no one is sure what the object once was.

A number of very tentative suggestions have been made as to what it MIGHT be (see below), but none have met with general agreement. So, the field is wide open for you to put forward your opinion.

The three bits of the mystery object fit together as follows:

The millefiori mount K545 has a rectangular hole and four small round holes on the back which match the rectangular protrusion and circular holes on the top end of the cylinder K1055, so K1055 clearly slotted into the back of K545. K545 is made up of two components, a base plate with a cloisonne garnet border and the top with the mounted glass checkerboard gem.  When these two components are separated, you can see that the rectangular protrusion passed through the base plate and into the back of the gem mount. The circular holes also appear in the back of the gem mount.

As already mentioned, the cylinder K1055 has the rectangular protrusion and four circular holes at the top end. At the bottom end are four matching circular holes and the torn remains of a silver plate with clear evidence that the same rivet holes also passed through it. The torn edge of this silver plate matches precisely the torn edge at the centre of a circular silver disc which was set at the inner apex of K130, showing that these two pieces of silver were originally one object, which means that K1055 and K130 joined.

K130, K1055 and K545

The elaborate gold piece K130 was originally circular and somewhat domed, but has been squashed, and rather damaged at one side. It is decorated with splendid cloisonne garnet designs and added gold plates with zoomorpic decoration of biting beasts. The silver disc was originally rivetted inside this, on the inner side of the domed top, by four rivets in the outer edge of the disc which fastened the disc inside the top of K130. The central part of the silver disc protruded through the hole at the centre of K130 and was in its turn fastened to the lower end of K1055 via four holes. Since these holes appear to run from the silver disc, through the entire length of the cylinder K1055 and right inside K545 as well, we are assuming these must have contained something like fixing wires rather than rivets. These must have served to anchor the whole construction together.

Rivet holes around the lower edge of K130 show that this was also fastened to another object, but there is no evidence to suggest what this might have been.

The construction is so complicated that it is very difficult at the moment to be sure in precisely what order the parts were assembled.

Suggestions as to what the mystery object might be include:

(1) A fitting on a saddle.

(2) The decorative tip to a shield boss, presumably from a very elaborate shield. (In this case the object would have been rivetted to the top / front of a standard iron shield boss. A warrior held his shield by grasping a handgrip that ran across a circular hole cut in the centre of the shield. The domed boss covered the hole while leaving space for the warrior’s hand inside.)

(3) A decorative top to a stopper that fitted into a drinking horn. (Here the object would have been rivetted to a wooden stopper that fitted inside the mouth of the horn.)

(4) A decorative terminal to a parchment roll. (I think the suggestion is that there would be one at each end of the roll, fixed to whatever the roll was attached to.)

(5) A lid to something. But what? (Again this probably requires the object being rivetted to something like a wooden stopper.)

Dr David Symons, curator at BMAG, Research Advisory Panel.

Blacksmith Simon Doyle

My name is Simon Doyle, and I am a blacksmith.  I am privileged to have gained an internship placement with Birmingham Museum whilst studying on a Heritage Ironwork course with the National Heritage Ironwork Group.

Whilst the work here bears little relation to what I normally do as a Blacksmith, the ethics and principles of conservation are very important.  I am going to come across historical ironwork during my career.  Being able to understand the role of a conservator as well as being able to do the work myself will stand me in good stead when working alongside museums and other conservation societies in the future.

Training

The first task as an Intern here at the museum was to clean and report findings on some sections of bone from the museum collection.

First task: Clean and report findings on section of bone.

The team here showed me the various tools at their disposal, and trained me on their appropriate use.  I am normally wielding a 3 pound hammer and a pair of tongs stood in front of an anvil, so the adjustment to working with a thorn held in a pin vice and using a microscope was interesting, although the basic skill set remains much the same, both requiring precision, concentration and an eye for detail.

Simon Doyle at work in the conservation studio.

Once all the work had been done on the bones, and the reports all written, I was presented with a dried up piece of earth.  This was also a training exercise, but essential to ensure that the skills I have learnt on the bones are put into practice on a metal object.

Second task: Training exercise in removing dirt.

The process of moving dirt grain by grain under the microscope then continued until my object, a humble looking (though doubtless of great historical significance) plug chain, was revealed!

Plug chain revealed as dirt is removed.

As well as the above mentioned work, I have been lucky enough to be involved with the taking down of a hoard exhibition at Tamworth Castle, and showing items of significance to some Saxon re-enactors and other VIP visitors.

The tools that I have used during the placement are worth mentioning, especially as many of them I had never encountered before.  As well as the already mentioned thorn in a pin vice, I have used:

• Chemical Sponge – a sort of plastic sponge
• Dental scrapers
• Toothpicks and cotton wool – used to make my own tiny cotton swabs
• Filtered water
• IMS – Industrial Methylated Spirits – Basically alcohol.
• Microscope – using it is a skill that I have had to quickly develop.
• Photo Micrographs – a camera attached to a very powerful microscope, which allows the recording of tiny objects, as well as being able to measure them.

Work on Hoard object K446

Having carried out the training, I was finally presented with my own piece of the Hoard to work on; K446, a partially revealed, though severely damaged, sword hilt plate, seemingly of gold.  Initial measurements, photographs and a pre-inspection report were prepared, and checked with my colleagues.  Removal of the dirt begins with the picking off of the larger grains using the thorn.  As I got nearer to the surface, a tiny swab with only the smallest amount of IMS was used to remove the dirt using the lightest and most delicate of touches.  Each grain of dirt seems to reveal something new or interesting about the item, and it is not hard to get carried away making fanciful stories in your head about how the item wound up in the condition it is in, and what each mark and scratch on the surface might mean.

K446 Sword Hilt Plate

The assessment of this piece is ongoing, and once the item has been fully revealed through conservation cleaning and documented, it will enter into the museums database.  It is a sobering thought that a 7th century sword hilt place made from gold is the piece I have been allowed to work on.  The fact that I am allowed to work on something so incredibly valuable and of such historical importance, has given me an amazing experience to remember and learn from.  I have particularly enjoyed looking at the items from a metalworker’s perspective, seeing how the craftsmen would have worked and shaped the metal to create the objects.  Many of the skills are the same for the stubborn and obstinate material I use regularly as for soft and malleable gold, and a real sense of connection to the craftsmen that made these items is the biggest reward I will take from this experience.

Simon Doyle, Blacksmith.

I have also had the chance to treat several objects. This blog post will detail two of these treatments, which demonstrate the boundless potential of the Staffordshire Hoard to surprise us and present new questions for further research.

Objects Before Treatment

Prior to treatment, the two objects in questions appeared to be constructed similarly (figs. 1 and 2).

Figure 1. K843 Lentoid Plate.

The first, K843, is a stunning lentoid made of gold and garnets, a possible pair to K270, treated by Deborah Magnoler and described by her in a previous blog post.

Figure 2. K682 Cloisonné Strip.

The second, K682, is a gold strip. Like the lentoid, it is embellished with cloisonné cells. The cells in both objects were heavily caked with soil prior to cleaning, obscuring the distinctive features of the pieces.

Treatment of K843

The lentoid was my first treatment, and it was a rather striking introduction to the Hoard. I began by examining the object and taking note of its condition and construction. Then I took photographs and wrote a brief report to document the object’s state before treatment. Certain features were apparent before removing the soil. The object was clearly designed to impress, with an estimated 239 cloisonné cells, gold backing foils stamped with two different patterns, and a double border of filigree around the outside edge.

In treating the lentoid, I followed a protocol that is fairly consistent for Hoard objects. Working at magnification levels from 7.5x to 75x, I used a natural thorn held in a pin-vice to carefully break up soil (fig. 3). Then I used a fine, soft brush to lift the particulate from the surface. Where necessary, I used a small amount of water or industrial methylated spirits (95% ethanol + 5% methanol) on a swab to help soften compact soil and remove residues.

Figure 3. Cleaning a garnet with a thorn 25x.

Everything that I removed from the object, including soil, organic material and corrosion products, was photographed in situ and retained in labelled sample vials. In the future, these samples may provide critical information through analysis. Prior to analysis, it is crucial to limit the introduction of modern materials to an object, but consolidation is sometimes necessary when elements are significantly loose or fractured. In treating the lentoid, I consolidated four garnets and one loose backing foil using tiny drops of Paraloid B-72, a reversible adhesive that is often used in conservation.

During treatment discoveries about K843

After treatment, the lentoid’s design can be fully appreciated (fig. 4) and its condition can be accurately assessed.

Figure 4. Lentoid K843 after treatment.

Altogether, 211 garnets remain in the object. Some cells are missing garnets or backing foils; and while this interrupts the design, it also reveals the astonishing intricacy of the object’s construction. In the empty cells, possible remnants of a backing paste exist. This would have bulked up the cells beneath the patterned gold foils into which the cut garnets were precisely set (fig. 5).

Figure 5. Garnets, backing foils and empty cells 7.5x.

Several rivet holes and one intact rivet, seemingly in its original location (fig. 6), indicate that the object would have fastened to a support of some kind. For the present, this object remains a mystery.

Figure 6. Extant rivet atop a silver divider 10x.

Treatment of K682

I began treating the cloisonné strip in much the same manner as the lentoid. Even prior to treatment, I made a number of observations about the object. The right end of the strip bends back on itself, and certain features suggest that the two short edges of the strip were originally joined to form an elliptical shape, which possibly would have been used as a hilt collar. One of the most compelling indications for this theory is the presence of excess border extending from the bottom edge on the right of the object and a lost portion of border at the bottom edge of the left side of the object.

Figure 7. Excess border measured at 13.44 mm 10x.

I took measurements of these two areas, and they are almost equal in length, about 13.4 mm (figs. 7 and 8).  I also found that the partial cells on the right edge matched up well with the partial cells on the left edge.

Figure 8. Missing border measured at 13.49 mm 10x.

During treatment discoveries about K862

Although the contents of the cells were covered in soil, they were, I assumed, likely to contain garnets. I did notice the presence of greenish deposits visible through the soil in a few of the cells, but similar green material was found on the lentoid, and these cells contained garnets (figs. 9 and 10).

Figure 9. Green material on strip in cell near top edge BT 25x

After the first few cells were excavated, however, it became apparent that this object was very different than the lentoid. None of the cells contain garnets.  Nor do they contain backing foils or any other evidence that they were once set with garnets. Instead, the large majority of cells are partially or completely filled with the compact green material that was only present in traces on the lentoid and assumed to be a corrosion product. After this discovery, I proceeded to remove the loose soil from atop the cells, but I left all of the green deposits in situ. Orange residues were also found in some of the cells, typically on top of the green material.

Figure 10. Green material on lentoid near bottom right edge BT 40x

These findings present more questions than answers. The elaborate cloisonné cells on the object must have been inlaid with something originally. The appearance of the deposits suggests copper corrosion products, possibly from a colorant in glass, but if the deposits are remnants of deteriorated glass, why have glass inlays survived in much better condition on other objects from the Hoard? Another theory is that the cells contained enamel. Enamel is essentially made by fusing powdered glass. The ratio of the components in enamel may be adjusted to change properties such as melting temperature. For example, with a high percentage of alkalis and low lime content, enamel will flow at lower temperatures but may be very prone to decay. Perhaps K682 was originally embellished with a beautiful but short-lived material like this. Further analysis by the British Museum science department will help to solve this mystery and other key questions surrounding the hoard.

Conserving the objects in the Staffordshire Hoard is a crucial step in piecing together their history. As more objects are conserved, we are able to identify candidates for in depth analysis and establish key relationships among individual artefacts. I feel privileged to be part of the team.

During my 9 week placement, I have also recorded video blogs of my experience, which focus on my work in the conservation studio as well as installing the Staffordshire Hoard on the Mercian Trail in Lichfield Cathedral.

Ellen Promise, Conservation intern from Winterthur/University of Delaware Program in Art Conservation.

XRF machines work by producing an X-ray that excites atoms on the surface of the object, in order to stabilise themselves these atoms then release energy which can be detected by the machine. Each element produces energy with a different wavelength, thus allowing the machine to tell them apart. The machine also counts each instance of energy being released for each element, thereby producing a spectrum with peaks whose size are dependant on the quantity of each element present. This can then be converted into percentage values for the composition of the object.

I recently analysed two hoard objects and presented here are the findings. I also captured this on a video blog, so you will be able to see me using the analyser.

K353 Gold Pommel

K353 Overview after edited

The object shown in fig. 1 above is the pommel of a sword or knife, a pommel is the part found at the very end of the handle. This pommel has been decorated with twisted wires in a technique known as filigree. The bright yellow colour of the metal suggested that it was very pure gold with little silver or copper present that can make it slightly pink or white. Analysis showed this to be the case with a large gold (Au) peak present on the spectrum shown below in fig. 2 and only very small peaks for copper (Cu) and silver (Ag). The result given was 94% gold which is around 22 carats. This is far higher than is usually used in most modern jewellery as gold is very soft unless it is alloyed with other metals. This may explain why the surface of this object is very worn in places.

Fig. 2 XRF spectrum for the surface of K353

Fig. 3 K353 Overview bottom after edited

On the interior of this pommel was a green powdery layer, this is indicative of copper corrosion and shows that the gold was placed around a copper alloy core to strengthen it. This is what allowed the Anglo-Saxon craftsman to use a thin layer of high carat gold without it being easily bent out of shape. Analysis of this green material did indeed produce copper but also tin (Sn) with a fairly large peak. An alloy of copper and tin produces bronze, a very strong metal that was widely used for many different objects although it had been superceeded by iron and steel for blades by this point. The high peak for iron (Fe) may well be from the soil which has not yet been excavated from the pommel interior at this point.

Fig. 4 XRF spectrum for the interior layer of K353

K64 Silver Edging

The object shown below in fig. 5 is a decorative silver edging that would have been riveted to a larger object. It is inlaid with a substance known as niello; a compound containing silver and/or copper and sulphur. It has also been gilded along the left side.

Fig. 5 K64 exterior after captioned edited

The spectrum produced on the silver surface inlaid with niello shown in fig. 6 indicates that the surface is mostly silver as would be expected. Although sulphur will be present as part of the niello it is unlikely to appear on this spectrum as it is a light element which produces low amounts of energy which may be absorbed before it reaches the XRF’s detector. This is where the British Museum science department will come into play, using their analytical equipment to further test this object’s composition.

Fig. 6 XRF spectrum for the silver surface of K64

The gilded surface shown on the left side of fig. 7 produced the spectrum shown in fig. 8 with large peaks in both gold and silver. This is because it is not only detecting the very thin layer of gold but also the silver underneath. This may be because the gilding is worn and scratched in some areas or simply because the gold is so thin that the X-rays can penetrate it to the silver beneath. With gilded surfaces one element we particularly look for is mercury, as this was commonly used to aid the gilding process at this time. However it would be present in such small quantities that our XRF may not be able to detect it even if it were present. This is another area that can be looked at in the future at the British Museum.

fig. 7 K64 Gilded surface detail after x7.5 edited

Fig. 8 XRF Spectrum for the gilded edge of K64

To conclude, although our analysis is relatively quick and simple it already gives us a good idea of the composition of these spectacular objects. As detailed briefly in this blog, this data can tell us more about the methods and materials involved in their manufacture. However further work is required and will be ongoing for many years, both here and in other institutions such as the British Museum, to glean as much information as possible from this highly significant find.

Graeme McArthur, Intern for the Hoard Conservation Team at BMAG and student at the University College of London.

The Keyence 3D digital microscope will not only help the Conservation Team with their work in Birmingham and Stoke but it will also benefit the Curators, and Researchers who may wish to view the surfaces in more detail.

There is a short video blog showing the equipment in use but for those that are interested here are some of the features:

• Large depth of field
• Rotational mount for viewing at angle
• Hand held option (larger items)
• Optimal lighting option, these highlight grain, surface texture (useful to pick up tool marks etc)
• Quality viewing screen (good for public tours, researchers)
• Has a split screen option to compare different areas or the same area at a higher magnification
• Has a range of lenses from 10x – 5000x
• Will capture 2D images, 3D images, , has 2D and 3D stitching (to create a larger image of the surface area) and video.
• The software allows measurements to be taken, so the depth and size and width of foils indents can be measured.

I have attached some images we were able to capture of a one of the tiny foils using the Keyence 3D digital microscope. The first shows the whole foil at x 50, stitched together. The next two show the detail at x50 and x200. The detail is fantastic.

Foil at x 50 (stitched together)

Detail of foil at x50

Detail of foil at x200

The images and videos produced will also allow us to share our findings with the public via the website and the displays in the galleries. So once again – a huge thank you to everyone!

Deborah Cane, Hoard Conservation Project Manager

Birmingham Museums and Art Gallery