Conservation at the Museum of Anthropology, Vancouver

Megan Narvey

The conservation program at UCL consists of two Master’s degrees over the course of three years. Two summers of those three years are consumed, more or less, with the writing of dissertations. The middle summer, however, is free. I’m Canadian, and although I’m very happy with my decision to study conservation abroad, I hope to work in Canada when I’m finished. Therefore, I used my free summer to build contacts in Canada by applying for an internship at one of my favourite Canadian museums.

The Museum of Anthropology (MOA) at the University of British Columbia in Vancouver, Canada, has an impressive collection of objects from all around the world, and is most well known for its collection of objects from First Nations groups of the Pacific Northwest. The museum is also known for having a very inclusive policy of working with the communities it represents.

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Haida house totem pole in the Great Hall, from c. 1870. These poles were originally from one pole, which stood outside the front wall of a house called ‘Plenty of Tliman Hides in This House’, a structure belonging to the family of the clan of ‘Those Born at Gadasgo Creek’, of the Raven moiety. Please read more about them on MOA’s online catalogue, here.

I had visited the museum before and was impressed with the collection, the quality of the facilities (there was a major renovation in 2010), and was intrigued by its use of a glass door separating the conservation lab from the galleries. It didn’t hurt that this is the view outside.

The view from the staff lunch area is not too shabby.

The view from the staff lunch area is not too shabby.

At MOA, I worked under the guidance of the conservators Heidi Swierenga and Mauray Toutloff. I completed complex treatments, worked with volunteers, and learned about and assisted with earthquake-proofing of the storage areas (this is not a problem you come across in London!). The most interesting treatment I worked on was of a Kwakwaka’wakw wooden figure.

Before treatment

The figure would have been displayed publicly to honour the greatness of a chief, and depicts a chief being carried on the shoulders of a slave. You can read more about the context of the object here. The figures are painted with red and black paint, and the wood – likely cedar –  has been stained or varnished. The figure needed conservation as, during handling, the thumb of the chief had fallen off due to a failed previous conservation treatment. At the same time, a curator had come across a historic image of the figure where the outstretched arm of the chief was held in a different position. The historic position was more in keeping with the original context of the object, so we were asked if we could return it to this previous position.

Detail of where the thumb had broken

Detail of where the thumb had broken

The first step of the treatment was to determine how the outstretched arm was connected to the body, and how to remove it without causing any damage. There appeared to be a lot of pieces of wood nailed together around the joint, as well as a bright, new wooden wedge and two different kinds of adhesive.

Detail of the arm joint

Detail of the arm joint

After plenty of examination, it was clear that the arm itself was not nailed in place, but only adhered. The adhesive was found to be soluble in ethanol, so it was softened with the solvent and the arm easily pulled out of the socket.

Stage one of the treatment accomplished!

Stage one of the treatment accomplished!

The next stage of treatment was to remove the tenon, of the open mortise and tenon joint, and reattach it at an angle that would put the arm in its historic position. The tenon was attached to the arm with an overly strong adhesive that was causing the wood on the arm to fracture, as well as with six nails. I removed the adhesive with solvent and had to pry the tenon away from the arm using wooden wedges and hammer. Then I removed the nails from the tenon by hammering them out backwards, with a piece of wood to cushion the blows so as to preserve the nails.

The slow process of driving wooden wedges between the arm and the tenon to separate them without causing further damage.

The slow process of driving wooden wedges between the arm and the tenon to separate them without causing further damage.

Both the arm and the tenon were pockmarked with holes from nails hammered in and removed over time. In order to lower my impact on the object, I chose to reuse two of these holes to attach the tenon to the arm in the new position, and used screws instead of nails, which are easier to remove. Finally, I removed the visually obtrusive wooden wedge and replaced it with a piece of 8-ply black acid-free matboard. No adhesive was needed to secure the arm in place.

The arm joint after treatment

The arm joint after treatment

The last step of treatment was reattaching the thumb. Upon examination, four different eras of previous conservation were detected (all prior to the object’s acquisition by the museum in 1973, and the establishment of the conservation labs at MOA). There were wooden wedges, nails, what appeared to be a type of animal glue, and then what appeared to be a more modern synthetic glue. All of these treatments had failed because the thumb lacked good contact with the body. Therefore, I decided to use a combination of fill and adhesive to reattach the thumb to the body, with a modern, easily reversible conservation adhesive.

The thumb, reattached more securely to the figure.

The thumb, reattached more securely to the figure.

After the treatment, the object was returned to its location on display in the Great Hall of the museum, with what I see as a much grander and more imposing appearance.

The object after treatment.

The object after treatment.

My internship experience at the Museum of Anthropology was highly educational and equally fun. To learn more about conservation at MOA or their conservation internship program, please find more information at http://moa.ubc.ca/conservation/.

A Heavenly Transformation – The Treatment Continues…

Jan Cutajar

Check out the previous posts in the series here, here, and here!

Our last blog post on the treatment of the Norfolk Museums Services angels dealt with some very satisfying flake relaying on Angel A. In this new episode, we shall delve into the treatment of Angel B (shown below in case your memory needs jogging), which had suffered a more severe case of surface delamination than its counterpart. Indeed, the delamination had reached such a severe state that even slights movements of the angel within its packaging resulted in notable loss of gilding!

Angel B, more affectionately known as Gabrielle. Courtesy of Norfolk Museums Service, T1878333.

Angel B, more affectionately known as Gabrielle. Courtesy of Norfolk Museums Service, T1878333.

For this reason, an intensive rescue operation took place earlier this year over three, wintery January days, with the aim of stabilizing the angel so that it may be removed from its packaging and be treated in a similar manner as Angel A. An enthusiastic team comprising of the author, Letty Steer and Dae-Young Yoo was put together and led by a motivating Claire D’Izarny-Gargas.

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The team members hard at work – above, from left to right, Dae-Young Yoo, Letty Steer & Claire D’Izarny-Gargas; below, from left to right, Jan Cutajar, Dae-Young & Letty.

The team members hard at work – above, from left to right, Dae-Young Yoo, Letty Steer & Claire D’Izarny-Gargas; below, from left to right, Jan Cutajar, Dae-Young & Letty.

Given the condition of the angel, it was slightly (if not very!) daunting to actually even consider touching the angel. The first step, therefore, was to develop a method of stabilising very loose flakes. After several initial trials, it was found that the best method, given the time frame we had to work in, was to apply a Japanese tissue paper facing (adhered directly with a 2% w/v solution of Klucel G in isopropanol, a hydroxypropyl cellulose adhesive commonly used with organic materials), which was then heat-activated using the heated spatula. This step allowed the gilding flakes to be slightly re-shaped in the process before relaying. You can see these facings in the pictures above – here are some more detailed shots of the procedure.

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Applying the Japanese tissue facing using 2% w/v Klucel G – where possible, the areas of flaking were cleaned first, as can be seen. Sometimes though, this was not possible and facing was applied directly to severely flaking sections.

Applying the Japanese tissue facing using 2% w/v Klucel G – where possible, the areas of flaking were cleaned first, as can be seen. Sometimes though, this was not possible and facing was applied directly to severely flaking sections.

The same procedure used to relay flakes on Angel A was then used, applying solutions and heating through the paper facing, which was possible due its fibre-thin nature. Once the gelatin (5% w/v in deionised water) had set hard after 5–10 minutes from heat-activation, the facing was removed by first moistening it with lukewarm deionised water and then peeling it off at a 180o angle with a pair of pointed tweezers. Any clean-up of excess gelatin or paper threads could then take place with warm water swabs.

Here’s an example of the complete treatment procedure: (1) flakes before treatment; (2) facing applied; (3) application of 50% IMS and gelatin, followed by heat activation; (4) after setting, the facing is removed with a warm, wet swab; (5) tweezers are used to pull the facing gently off; (6) the area after treatment, success!

Here’s an example of the complete treatment procedure: (1) flakes before treatment; (2) facing applied; (3) application of 50% IMS and gelatin, followed by heat activation; (4) after setting, the facing is removed with a warm, wet swab; (5) tweezers are used to pull the facing gently off; (6) the area after treatment, success!

Once we were confident that this method worked, the angel in its packaging was set on the operating table and the areas identified as most fragile were faced and treated. There definitely was a ‘surgical theatre feel’ to all this, with two conservators each working on each side of the box, passing around spatulae, brushes and adhesive solutions. Everyone fell promptly into their roles and the rhythm of work got going.

Here, Claire and Dae-Young are stabilising the angel, before its removal from its temporary packaging.

Here, Claire and Dae-Young are stabilising the angel, before its removal from its temporary packaging.

The “operating table” so to speak, with different parts of the treatment taking place at the same time.

The “operating table” so to speak, with different parts of the treatment taking place at the same time.

Letty and Young heat activating the Klucel G and gelatin using heated spatulae.

Letty and Young heat activating the Klucel G and gelatin using heated spatulae.

After the first day, the angel was lifted out of its box successfully without any severe loss of gilding. This allowed us to access more surface area on the angel and so the work intensified during the next two consecutive days, as you have seen already in some of the photos. Facings were applied, flakes were relayed and facings taken off. The most challenging areas were the face, wings, chest and feet on the angel due to the undulating surfaces and level of decorative carving. At times, some flakes were broken or damaged during treatment which was heart-wrenching, however, the solution to this was very straightforward: document it and then repair it.

Some stunning work achieved by Claire on the face of the angel.

Some stunning work achieved by Claire on the face of the angel.

Similar successes on the left wing – clearing the facing was particularly tricky here, as it tended to catch on the decorative carvings, lots of care and caution were thus necessary to achieve these results!

Similar successes on the left wing – clearing the facing was particularly tricky here, as it tended to catch on the decorative carvings, lots of care and caution were thus necessary to achieve these results!

At the expiry of the available time, the angel was miraculously looking in much better shape than before, and in turn was also much more stable! Indeed, the success of the treatment allowed us to move the angle from a lying, horizontal position to a standing, vertical one. Advantageously, this then permitted an improved packaging solution to be implemented whilst more work was carried out at a later stage.

The angel after three days solid work – and finally standing whole!

The angel after three days solid work – and finally standing whole!

Yes, despite the advances made at this stage, the treatment was not yet over and further relaying of gilding and paint was necessary. This was completed in part during another similar session in February. In fact, should you wish to know about this session, we will be more than happy to answer your questions in person at this World Archaeology Day Festival at the UCL Institute of Archaeology, come Saturday the 13th June! There’s an even more exciting part though! We shall be working on the angels this Saturday and you will have the opportunity to see how this work is done in real-time. So don’t miss out on this fantastic opportunity to set your eyes on these angelic beauties, we look forward to seeing you!

WE LOOK FORWARD TO SEEING YOU THIS SATURDAY!

WE LOOK FORWARD TO SEEING YOU THIS SATURDAY!

N.B. All photos by Claire D’Izarny-Gargas & Jan Dariusz Cutajar. Permission to post courtesy of the Norfolk Museums Service.

Material Spotlight: Agar Gel

Robert Price

I’m just going to come out and say it – gels are pretty amazing.

Jurassic Park (1993)

Jurassic Park (1993)

No, not this kind…

I mean, sure, Jell-O or Jelly is pretty great too, but I’m talking about the gels used in conservation and my new favorite gel – Agar.

If you’ve done some lab work you’ve probably come across Laponite RD (a synthetic clay), Carbopol (a carbomer resin), or Cellulose Ethers like Methyl Cellulose or Sodium Carboxymethyl Cellulose being converted to gels for cleaning techniques involving water, solvents, or other cleaning agents.

Gels are useful because they minimize the total amount of solvent or water needed for a treatment by slowing the rate of evaporation and maintaining good contact with the surfaces targeted for cleaning – this is good for you, the environment and the object. In some circumstances gels can also have a poulticing effect and are capable of absorbing a portion of the materials they solubilize or soften.

Aside from potential chemical interactions, a big consideration with gels is how easily you can remove them once they have worked their magic – a process known as ‘clearance’. With some gels this might be particularly problematic, especially when used on very rough or porous surfaces. Not all gels are the same though and you need to do some research.

But here’s where my new favorite material comes in – enter, Agar gel.

If you look into the literature you might be surprised to see the wide range of materials it has been used to clean, including: wax sculptures, marble, gypsum plaster, ceramics, wood, and textiles. Anecdotal reports from our peers currently undertaking work placements have also noted its growing use within museums, especially for surface cleaning on limestone.

The beauty of the gel is that it’s capable of slowly releasing water in very small amounts, which means that it can be used to remove or soften water-soluble materials without overly saturating a water sensitive surface. Unlike other commonly used gels, the rigid gel formed by Agar is extremely easy to remove in a single piece and leaves no visible residues behind. This minimizes the amount of mechanical action needed to clear the gel. You should be aware, however, that at least one study has identified trace amounts of polysaccharides within cleaned materials analyzed with GC-MS.

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Comparative clearance tests with commonly used gel concentrations on Melinex

Personally, I have found it to be a promising material for softening and removing proteinaceous glues in situations where excessive amounts of water or heat would be problematic for the object being treated – as is the case for bone and wood.

It’s definitely worth experimenting with, even if you don’t currently have a use for it. While purified agarose can be purchased online, food grade Agar is much cheaper and can be purchased from higher end grocery stores. Even some high profile cleaning projects have gone with this cheaper alternative. I’ve been using Clearspring® Agar Flakes.

Try making a 2% w/v gel by adding 2g of agar flakes to 100ml of boiling water and a allowing the solution to cool within a flat container. The resulting sheet can be cut into whatever shapes you need and will keep in the fridge for a week or more depending on the cleanliness of your equipment and how often you open the container.

A square of Agar gel, roughly 3mm thick.

A square of Agar gel, roughly 3mm thick.

Unfortunately, these tidy little sheets only work well on flat surfaces. As an alternative, the semi-cooled solution can also be placed in a plastic syringe and extruded just before gelation occurs, allowing the gel to better conform to complex surfaces. This takes some practice and familiarity with the material but can be very effective.

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Direct application of the gel near its ‘sol-gel’ transition temperature.

Finally, you can also experiment with forming the gel around other materials as I did with natural fiber strings. The string can be repeatedly dipped in and out of the warm solution until a thick coating is formed around the fibers. Strings with looser twists and greater surface area work best. This gives the gel a support structure and made handling and removal even easier. Possible applications could be for disassembling narrow joins or lying over curvilinear shapes.

Non-dyed, natural fiber strings used as ‘scaffolding’ for the gel

Non-dyed, natural fiber strings used as ‘scaffolding’ for the gel

Hopefully this has been helpful and got you excited about exploring Agar gel further. It might be a good alternative to consider the next time you have to remove proteinaceous glue from a fragile or water sensitive surface.

 

 

Breathing new life into a solvent dispenser

Dae-Young Yoo

In our lab, we frequently hear “does anyone have extra acetone? IMS? White spirit?” Here, the solvents do not mean just solvents, it actually means a solvent dispenser filled with a specific solvent. Why is this such a frequent problem? Let’s find out the reason and sort it out!

Solvent dispensers have been used in conservation labs for some time. These are pump action bottles that allow the controlled use of solvents during lab work. There are many advantages to using these dispensers. Firstly, it makes the controlled application of solvent to cotton wool swabs or brushes much easier, without contaminating the rest of the solvent . The pump on the dispenser transfers a small amount of liquid to the cup at the top. Therefore, there is no need to worry about an excess of solvents or accidental spillage. There are health and safety advantages to using solvents in this way, as it reduces the evaporation rate of solvents, and reduces potential exposure to solvent fumes. Lastly, it is made of plastic which makes the dispenser shatterproof. Even if you drop the dispenser, it remain as it is without gushing solvents out of it.

A solvent dispenser can control the amount of solvent. It makes it easier to apply cotton wool or brush (photo courtesy of Dae Young Yoo)

These solvent dispensers are very useful for conservation practice and routinely used in the UCL Conservation lab. So when they go wrong it usually results in a frustrated cry for help. One major drawback of the solvent dispenser, is the durability of intake tube inside the dispenser bottle. I am not sure if this problem applies to all dispensers in the world. However, most dispensers I have used fail to function because of a problem with the tube, rather than other parts of the dispenser. Most of the broken dispensers in my lab have the same problem. So I figured out why so many classmates end up suffering while pushing the dispenser pump to no effect, and then ending up ’borrowing’ other classmates dispensers. It is really annoying that something does not work properly when necessary.

In this post, I will let you know how to fix it, with materials that are easily available in your lab or workplace. It is super easy and only takes three minutes to fix . I hope this post helps not only my classmates, but also conservators fix broken dispensers by themselves, and therefore remove one element of conservation lab stressing out.

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A crack on the tube reduces air pressure in the tube when the pump at the top is pressed. The principle of pump is the air pressure difference between inside and outside of a tube. Because of the crack, the air pressure between inside and outside of tube is the same, which makes it difficult to suck up solvent in a dispenser (photo courtesy of Dae-Young Yoo)

How to fix it

Everything you need:

– A disposable pipette made of low-density polyethylene (LDPE, which has resistance to acetone, ethanol, white spirit and IMS)

(Note: You should check what your disposable pipette is made of and what types of solvents will be used because some plastic pipette are easily dissolved in some solvents)

– A hot air blower, or a lighter in extreme situations where a hot air blower is not available

– scissors

  1. Heating a pipette

Heating a pipette with a hot air blower.  (photo courtesy of Emily Williams)

Ensuring you have first carried out a risk assessment, and have access to suitable Personal Protective Equipment and fume extraction, heat a disposable pipette with a hot air gun until the colour of pipette becomes transparent. Turn the pipette to ensure that the area is evenly heated. Do not heat just one spot, otherwise the pipette will be burn. In addition, before heating it, you have to consider the height of a dispenser and decide the location of the pipette for heating.

  1. Pulling a pipette
When the heat is applied, the pipette get transparent and soft (photo courtesy of Emily Williams)

Pulling a pipette while it is warm. When the heat is applied, the pipette gets transparent and soft (photo courtesy of Emily Williams)

The pipette is made of polyethylene, which is a thermoplastic polymer. The thermoplastic can be soft when heated and hard when cooled. We will take advantage of the properties of thermoplastic.

Pull the pipette from both sides considering the diameter of the solvent intake. You have to adjust the length of the pipette before it is cooled otherwise it will get hard in a short time so you cannot transform the pipette.

  1. Cutting a pipette with scissors
Separated pipette (photo courtesy of Dae-Young Yoo)

Separated pipette (photo courtesy of Dae-Young Yoo)

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Separated pipette (photo courtesy of Dae-Young Yoo)

  1. Replacing the broken tube with a new one
The pump with a new intake tube (photo courtesy of Dae-Young Yoo)

The pump with a new intake tube (photo courtesy of Dae-Young Yoo)

Replacing the tube is easier when the tube is warm. Otherwise the tube will get hard and could be difficult to fit it into the intake of the pump.

  1. Installing the new pump

(photo courtesy of Dae-Young Yoo)

Solvent dispensers with newly made tubes are working well in our lab. From now on, if you find a solvent dispenser broken, do not throw it away, and pinch another from your lab mates. Check the intake tube inside. If it is broken, just spend three minutes to fix it. Just three minutes will make the dispenser semi-permanent and save money (the price of solvent dispenser is usually over 10 pounds!!).

 

The Polishing Rush

Anna Funke

The last weeks of term are always a challenge in getting everything finished, but this term one task in particular – polishing SEM samples – took its toll on everybody’s patience.

The SEM (Scanning Electron Microscope) is a powerful analytical tool for our work. However, the sample preparation process is rather tedious. Just a quick reminder, a scanning electron microscope uses an electron beam (rather than light with standard optical microscopy) to produce images up to 500,000 x magnification.

Although there are several different methods for preparing these samples, our technique involved mounting our samples in resin (Clear Casting Resin POLYLITE 32032-00 from Alex Tiranti Ltd., to be specific), using ice-cube trays as moulds.

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Resin-cast samples of glass beads prepared by Emily Williams.

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An SEM image of the above sample, as prepared by Emily Williams. The glass appears grey in this image, and the swirls show that the glass was poorly mixed. The white specks in the sample are unmelted metal colorants in the glass.

Once cast, the resin block has to be prepared and sawn into the correct shape. This often requires some elbow grease and several sacrificial saw blades. The sample is then polished to the smoothest possible surface. This required four grades of abrasive paper, followed by 4 grades of micro mesh that added up to a good 5 hours per sample. One of the challenges is to make sure you are not left with scratches all over your sample.

The polishing work station of Megan Narvey.

The polishing work station of Megan Narvey.

The author and Megan Narvey discovering a significant amount of scratches on their samples.

The author and Megan Narvey discovering a significant amount of scratches on their samples.

At the end this long process you should have a shiny smooth resin surface, and are likely to have repetitive strain disorder. But if, against all odds, you do succeed in preparing a beautifully smooth surface, the images you will get in return for your labour are really quite amazing!

Sample of a cross-section of a painting by Kristen Gillette. Layers 1, 2, and 3 are surface pigments, probably acrylic paints; Layer 4 is a pigment ground layer; Layer 5 is the ground; and Layer 6 is animal skin.

Vanessa Applebaum’s cross section of painted plaster along with elemental maps of the sample.  Explain what can be seen here

Vanessa Applebaum’s cross section of painted plaster along with elemental maps of the sample. The cross section shows the plaster, applied pigment, and a carbonation layer. The elemental maps identify where specific elements are located in the sample. They are, starting from the top and moving left to right: silica, iron, chlorine, calcium, titanium, aluminium, potassium, and sodium.

Discover What is in Your Lab: Unlabelled Blue Pigment

Julie Flynn

As part of an assigned research project in the conservation materials science course, I was given an unknown bright blue crystalline material. The original context of the sample was unknown, but it was assumed that it was a pigment, possibly Egyptian Blue. Visually comparing my sample to a known sample of Egyptian Blue, it was obvious that they were not the same. In order to demonstrate this, I began investigating this unknown blue using various techniques available to me at the Institute of Archaeology at UCL.

The bottle of unknown blue pigment

The bottle of unknown blue pigment

Polarised Light Microscopy (PLM) was the first technique that I used to examine the sample. In this technique a prepared sample is illuminated under magnification with polarised light.

For comparison, here are the PLM images of the unknown sample and the known Egyptian Blue. Out of all the known samples I analysed, Egyptian Blue pigment had the largest grain size. However, as you can see in these two images at the same magnification, the unknown sample still has much larger grains!

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PLM image of the unknown sample

 

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PLM image of Egyptian Blue

The unknown blue has grains at least twice as large as the Egyptian Blue. The other known samples of blue pigments in the lab had even smaller grains – smaller than 10 µm in length.

I was able to carry out elemental analysis using both portable X-Ray Fluorescence (pXRF) and Scanning Electron Microscopy with Energy Dispersive X-Ray Spectroscopy (SEM-EDS). In pXRF, secondary electrons in a sample are excited by bombarding the sample with high energy x-rays. Each element fluoresces differently, making this a good elemental analysis technique. IN SEM-EDS, an electron beam is scanned over the sample’s surface, and the electrons striking the sample produce signals. These specific signals can identify specific elements. Here are the results for identifying the blue portion of the samples.

Major Elements Found Within Pigments With Two Methods of Elemental Analysis

Pigment SEM XRF in Mining Mode
Unknown Pigment O, Na, Cu Cu
Egyptian Blue O, Cu, Si, Ca Si, Ca, Cu

The elemental composition of the two samples are different therefore, at this point, I believed that the unknown blue was not Egyptian Blue.

Now that I had established that the unknown sample was definitely not Egyptian Blue, I needed to find out what it was. For this, I used Energy Dispersive X-Ray Diffraction (EDXRD) to determine the unknown blue sample’s chemical composition. EDXRD uses X-Rays to reveal information about the crystal structure of the sample, which in turn reveals information about the sample’s chemical composition.

When I analysed the sample using EDXRD, the ICDD (International Centre for Diffraction Data) database of minerals found a very close match to the composition and crystal structure of the unknown blue pigment: sodium copper carbonate (Na2Cu(CO3)2).

 

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EDXRD diffractogram comparing the unknown blue sample to sodium copper carbonate (Na2Cu(CO3)2). This mineral matched closely to the chemical composition of the unknown blue sample. It also matches the results from the prior elemental analyses.

There is a rare mineral of sodium copper carbonate known as Juangodoyite. This mineral was discovered in situ in a Chilean mine in the Atacama Desert in 2003 by Arturo Molina, Iquique. It is formed by the dehydration of chalconatronite, which has the chemical composition of Na2Cu(CO3)2•3H20, and is a corrosion product of bronze. There is no evidence to suggest that this mineral has ever been used as a pigment.

Besides elemental and chemical composition analyses, more evidence that the unknown blue sample is juangodoyite is that they both form in crystals and have a bright ultramarine colour. Evidence against the unknown blue sample being Juangodoyite is that the minerals found in the Atacama Desert were 5 µm in grain size, which is much smaller than the unknown blue sample.

It’s curious to consider how this rare mineral came to UCL in the first place. Its origin at the Institute of Archaeology is shrouded by age, having passed from one professor to another professor many years ago under the name “Egyptian Blue”. It could have come from one of the Institute’s many international expeditions, or from a previous experiment to create a historic type of blue pigment. There are many possibilities – what do you think?

 

Let the Treatment Begin!

Abigail Duckor

Following the research conducted by Claire d’Izarny-Gargas, further examination led to the formation of treatment plans for Angel A and Angel B. As discussed earlier, Angel A was in decidedly better condition, so it was tackled first.

Claire starting the treatment on Angel A

Claire starting the treatment on Angel A, courtesy of Norfolk Museums Service, T1878333.

On the front and the back of the angel were two different types of surfaces. The front was a gilded layer, which was flaking and delaminating. The back featured a painted layer, also undergoing flaking, but not as extensively. The front and the back of Angel A therefore underwent different treatments. This blog post discusses the relaying of the flaking gilded surface. For the front of the angel the main goals were to clean the surface (which was very, very dirty!) and to relay the remaining flakes. An initial gentle clean was done with a cotton wool swab and a solution of 50:50 IMS (industrial methylated spirit) and deionised water. This method was selected after some cleaning tests were carried out in an inconspicuous area.

Cleaning tests on Angel A.

Cleaning tests on Angel A. Courtesy of Norfolk Museums Service, T1878333.

The flakes were then relayed by first saturating the area with the 50:50 IMS/ deionised water solution. Then, using a small brush, a drop of warmed gelatin solution (5% w/v in deionised water) was placed under the flake. Saturating the area first reduced the surface tension and allowed the gelatin to penetrate under the flake.

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The gelatin was dissolved in warm deionised water. It was kept at 60°C in a water bath. Photograph by A. Duckor

After the gelatin cooled a bit (a few minutes), heat was applied to the area with a heated spatula. A piece of silicone-release paper was used between the  spatula and the angel, to prevent damage to the surface from the tackiness of the gelatin. Pressure was gently applied to the flake with the heated spatula, in a ‘rubbing’ motion. The gradual heating softened the gilding and allowed it to be re-shaped onto the surface of the angel. The heat ‘activated’ the gelatin and adhered the flake onto the substrate.

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The heat spatula and brush used in the flake relaying. Photograph by A. Duckor

This method was very successful in relaying the flakes with little breakage. Following re-laying, further cleaning could be done without risking additional damage to the surface.

The left hand of Angel A before and after the flake relaying. Courtesy of Norfolk Museums Service, T1878333.

The bulk of this treatment took place during the summer months of 2014 and allowed for the involvement of both MSc and MA conservation students – a great opportunity to work together and learn from one another!

Erin Murphy using the heat spatula to gently press down a flake and seal it with the gelatin.

Erin Murphy using the heat spatula to gently press down a flake and seal it with the gelatin. Courtesy of Norfolk Museums Service, T1878333.

Rachel Altpeter and Romina Quijano Quinones working together.

Rachel Altpeter and Romina Quijano Quinones working together. Courtesy of Norfolk Museums Service, T1878333.

Yuqi Chock applying gelatin to flaking areas of gilding.

Yuqi Chock applying gelatin to flaking areas of gilding. Courtesy of Norfolk Museums Service, T1878333.

Photographs by A.Duckor and Claire D’Izarny-Gargas.

Work Placements – transitioning from the UCL conservation lab to a professional institution

Veronica Ford

So far in this blog we have seen a lot of stuff from the current inhabitants of the UCL conservation lab. As you know from Megan’s introductory post, the MSc in Conservation for Archaeology and Museums is actually a two year course.

“But what about last years’ lab students? What are they doing?” I hear you cry.

In the second year of the MSc for Conservation for Archaeology and Museums, students are assigned work placements lasting a total of 10 months to give them experience of the reality of the working environment (in other words – it’s a wake up call!).

My placement has been divided between two institutions. Between September and December, I spent time with the preventive conservation team within the Bodleian Libraries. From January onwards, I’ve moved on to the Ashmolean Museum of Art and Archaeology, both institutions located in Oxford.

The past six months have been a massive learning curve!

When people think of conservation they might imagine a lab-coated conservator gluing an object back together.

Something like this. Which sometimes is the case, nevertheless (photo courtesy of Naomi Bergmans).

Something like this. Which sometimes is the case, nevertheless (photo courtesy of Naomi Bergmans).

But in reality the role is far more diverse than that!

The two institutions I have been hosted at have been quite different (though very close to each other geographically). At the Bodleian, I was part of the preventive conservation team, ensuring that objects are kept in good environmental conditions (including temperature, humidity, light exposure, and so on) and that they are well stored and handled in order to minimise damage. I was also involved with the environmental proving of a new library building. This meant consulting with builders, contractors, other conservators, librarians, and curators. It also required a scientific approach to understanding the environmental factors that might adversely affect the storage of library materials. As part of this we implemented a dust monitoring programme in the new library, and carried out research into pest eradication.

The view from my office in the Bodleian wasn't half bad (photo courtesy of Veronica Ford).

The view from my office in the Bodleian wasn’t half bad (photo courtesy of Veronica Ford).

At the Ashmolean, however, I have focused more specifically on interventive conservation (i.e. the active treatment of deteriorated and broken objects). In addition to object treatments, I have been involved in a broad range of museum activities including pest monitoring, condition assessments, loans and exhibition installations.

No complaints about my view from the Ashmolean either (photo courtesy of Veronica Ford).

No complaints about my view from the Ashmolean either (photo courtesy of Veronica Ford).

The two experiences combined have shown me the true breadth and diversity of activities with which conservators are involved. Basically – we need to be involved whenever there is a risk that an object might be/has been damaged. Conservation treatment work needs to be fitted around this, as conservators are often required to jump in and get involved with other museum activities at the last minute. This is in contrast with my experience working in the conservation lab at UCL, where the majority of my time was spent actively working on object treatments.

At UCL, I was encouraged to gain experience with extensive research, complex analysis and challenging treatments. The need to develop hand skills and experience meant I was encouraged to undertake complicated treatments. This contrasts to some degree with my experience at a working institution, where the focus of treatment decision making is defined by the needs of the institution, and where time and resources may be limited.

Two previously restored ceramics with two different approaches (before treatment). Left - that undergoing treatment at the Ashmolean. Right - that treated at UCL (photos courtesy of Veronica Ford).

Two previously restored ceramics with two different approaches (before treatment). Left – that undergoing treatment at the Ashmolean. Right – that treated at UCL, Copyright UCL Institute of Archaeology Collections (photos courtesy of Veronica Ford).

This is clear in my approach to two archaeological ceramics both with broken Plaster of Paris fills, one of which I treated at UCL and one of which I am currently treating at the Ashmolean. My approach at UCL was thorough: I removed the old adhesive from the ceramic and reconstructed it from the beginning with conservation adhesive (Paraloid B72*), creating structural fills only where necessary. At the Ashmolean, I have decided to replace and repaint the broken fills, avoiding a complete deconstruction. This conserves time and resources and offers the least interventive approach, whilst still stabilising the object and fulfilling treatment goals.

I have learnt that it is necessary, in a professional context, to be pragmatic and realistic. This however need not be an obstacle to more in-depth research projects. The Ashmolean is always looking for new ways of researching and analysing the collection and recently received funding to carry out analysis on 500 objects belonging to the recently acquired Wellby collection.

It is hard to be glamorous when you work on a building site: moving special collection material into the new library building (photos courtesy of Veronica Ford and Naomi Bergmans).

It is hard to be glamorous when you work on a building site: moving special collection material into the new library building (photos courtesy of Veronica Ford and Naomi Bergmans).

At times conservation work can seem unglamorous or routine. But such activities are absolutely vital for the preservation of collections. For instance, an important preventive conservation activity is condition checking new acquisitions, to ensure that they are not actively deteriorating and can be safely stored with other collection material. This can sometimes result in rather difficult and less pleasant working conditions.

Spores for thought: checking new acquisitions for mould at the Bodleian (photo courtesy of Veronica Ford).

Spores for thought: checking new acquisitions for mould at the Bodleian (photo courtesy of Veronica Ford).

Conservation is often a controversial activity and it can be hard to balance established conservation approaches with increasing pressure on heritage institutions to maximise access to, and use of, collections. I am finding that essential conservation skills include the ability to negotiate with others, to communicate conservation needs clearly and accurately, and also to show willingness to be flexible and compromise where necessary. Although, in theory, this is clear to many conservators in training, the lesson cannot truly be learnt without direct experience.

* An ethyl methacrylate copolymer. Just in case you are wondering.

Acknowledgements: Thanks to my lovely work placement hosts at the Bodleian and Ashmolean and to Naomi Bergmans for some of the photographs.

A Glass Puzzle from Tell Fara

Emily Williams

Image Of The Glass Sherds Before Treatment. Copyright UCL Institute of Archaeology Collections

When I first came across the box full of archaeological glass fragments in the conservation lab, it raised a strong sense of curiosity and concern – I did not want the box of bits to go back to the collections store in the same condition, and without knowing what this golden iridescent glass used to be. The box contained 19 fragments, too few to make up a whole vessel, so early on, I had to abandon any idea of being able to reconstruct a complete object. After many hours of research, and what felt like the longest, most complicated puzzle I had ever done, I was however able to piece enough fragments together to infer the shape of a bottle.

Reconstructing the bottle. Copyright UCL Institute of Archaeology Collections

Once I had identified that the fragments formed a bottle, I attempted to reconstruct it. The glass was however too fragile to handle without the surface layers becoming detached. Before I could do anything else, I needed to consolidate the surface. This was done using very low percentage of Paraloid B 72 in acetone. I carefully applied this solution so that the polymer went under the delaminating flakes in order to reattach them to the underlying glass.

Making the Fill using Japanese Tissue. Copyright UCL Institute of Archaeology Collections

After I consolidated the surface, I put the fragments together with a more concentrated solution of Paraloid B 72. Stronger epoxy adhesives are often used to reconstruct glass objects in collections (like Hxtal NYL-1), but was not used with this archaeological object as the treatment would not have been so easily reversible. The potential for conservators in the future to retreat our conserved objects is always considered when we make decisions about our treatments now. I then used watercolour paints to colour Japanese tissue a very pale blue/green and sandy yellow in order to match the colour of the glass underneath the layers of corrosion. The tissues were shaped by hand, cut to size, and then attached as a support to the reassembled glass fragments.

The Reconstructed Base of the Bottle. Copyright UCL Institute of Archaeology Collections

For the upper section of the bottle, I experimented using a light bulb as a base to create my rounded fill. Shaping Japanese tissue so that it remains curved can be quite tricky. My lab partner Robert suggested I coat the light bulb in a thin layer of silicone to create a barrier between the two, this allowed me to remove the tissue from the light bulb surface once it had dried. I used T40 Silicone Rubber from Tiranti, which is a two part thixotropic mixture with a curing time of approximately 30 minutes.

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Using the Silicone covered light bulb as a mould for a Fill

One complicated aspect of the reconstruction was having to figure out how to reconstruct a closed vessel when the only opening was through the very small and narrow neck of the bottle. Once I had all my tissue supports in place, I inserted a bent wooden stick with a flattened silicone tip so I could reactivate the adhesive with acetone and use the silicone tip to press the tissue onto the glass from inside the bottle.

Glass Irridescence On The Inside Of The Bottle. Copyright UCL Institute of Archaeology Collections

Finally, the glass bottle reconstruction is now complete! The object will be returned to the UCL Institute of Archaeology’s Palestine-Petrie Collection, and is now readily available for teaching and research.

Image of the Bottle After Treatment. Copyright UCL Institute of Archaeology Collections

The Writing on the Sherd

Megan Narvey

One of the objects I am in charge of this year is this small ceramic pot, belonging to the Petrie Museum of Egyptian Archaeology:

Before Treatment photo of the archaeological ceramic in question. Courtesy of Petrie Museum of Egyptian Archaeology, UC65224

Before treatment photo of the archaeological ceramic in question. Courtesy of UCL, Petrie Museum of Egyptian Archaeology, UC65224

One of the interesting things about this object is that it was excavated by a rather famous early archaeologist, Sir William Matthew Flinders Petrie. Petrie is famous in archaeological circles as a pioneer of modern archaeology, implementing methodical techniques and caring about the small details.

Portrait of Sir William Matthew Flinders Petrie, 1903

Portrait of Sir William Matthew Flinders Petrie, 1903

Petrie’s legacy was visible right on the inner wall of one of the large sherds on my pot – the blue pencil markings were identified as belonging to him. Unfortunately, they are very difficult to read.

This blue pencil writing belongs to Flinders Petrie. Courtesy of UCL, Petrie Museum of Egyptian Archaeology, UC

This blue pencil writing belongs to Flinders Petrie. Courtesy of UCL, Petrie Museum of Egyptian Archaeology, UC65224

The pot had undergone a previous treatment some time in the past that had now failed, leaving several sherds detached, as you can see in the first photograph above. Additionally, the pot had survived not one, but two historic fires! This had left a thick layer of soot on the object, which you can see below. In order to remove it, I had to spend a lot of time testing different cleaning methods and looking at the surface of the ceramic very closely.

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Courtesy of UCL, Petrie Museum of Egyptian Archaeology, UC65224

There was an exciting and unexpected consequence of spending a lot of time cleaning the sherds –  I saw strange shimmery lines underneath engrained soot on one of the fragments, almost invisible to the naked eye. In order to figure out what I was seeing, I looked at the fragment with an infrared (IR) Dino-Lite, a handheld digital microscope. The infrared rays, with a longer wavelength than visible light, allowed me to not only see more clearly, but take close up images of what was hiding under the soot.

Here is an image of the sherd under normal light:

An image of the fragment with the hidden writing. Can you spot it? Courtesy of UCL, Petrie Museum of Egyptian Archaeology, UC65224

An image of the fragment with the hidden writing. Can you spot it? Courtesy of UCL, Petrie Museum of Egyptian Archaeology, UC65224

In contrast, here is what was captured with the IR Dino-Lite:

The IR Dino-Lite images of the hidden writing.

The IR Dino-Lite images of the hidden writing.

I also annotated the photograph on Powerpoint so that the writing was bright red, making it easier to read:

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Whatever is written here is very similar to and in much better condition than the original and much more obvious writing, even under the same conditions!

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I now need to help to identify what is written. What do you think? Can you decipher what Petrie has written?