Camille Polkownik – Hamilton Kerr Institute student and intern blog

The grass is always greener on the other side: conservation of the Portrait of Elisabeth de Valois

This oil painting on oak panel representing Elisabeth de Valois is a copy of the famous portrait originally painted by Anthonis Mor (c. 1517-1577), a Netherlandish portrait painter active mid-16th century (Fig. 1). The painting belongs to the Fitzwilliam Museum, and came to the Institute for assessment before the exhibition: Degas: A Passion for Perfection (3 October 2017 – 14 January 2018).

Fig. 1. Portrait of Elisabeth de Valois, copy after Anthonis Mor by unknown artist, late 16th century, Fitzwilliam Museum. (© Titmus) — Fig. 1. *Portrait of Elisabeth de Valois*, copy after Anthonis Mor by unknown artist, late 16th century, Fitzwilliam Museum. (© Titmus)

Elisabeth de Valois (1545-1568) was the eldest daughter of Henry II of France and Catherine de Medici and married Philip II of Spain as his third wife when she turned 14. The original portrait was painted by Mor in 1565, when she was 20. Elisabeth died at 23, after miscarrying for the second time in 1568.

The Fitzwilliam portrait, although not by Anthonis Mor, is a faithful copy in a style extremely close to that of Mor. The original portrait has been copied many times by different artists with varying degrees of accuracy. The copies highlight her importance and maybe her popularity, and were likely made to be sent around Europe to the various Royal Courts. The copies of the original portrait (Fig. 2) show her in this exact costume, but the formats vary: portraits only, full length, half length… you name it! The Fitzwilliam version was acquired in 1909, along with a full length portrait of her husband on canvas.

Fig. 2. Collage of all the portraits of Elisabeth de Valois

Dendrochronology

Dendrochronology analysis was done to find out an approximate date of usage for the panel. Dendrochronology (or tree-ring dating) is the dating technique that utilises the pattern of rings widths within a timber to determine the calendar period during which the tree grew. This is then matched to an existing database. The date of a tree-ring sequence must not be confused with the date of usage of a tree, as sapwood (which has the latest growth rings) is usually removed by panel markers. The analysis provides either a felling date range (when sapwood is present) or a terminus post-quem (when the sapwood is not present). Between the felling of the tree and the start of a painting, a fair amount of time can go by, as the wood travels and is often seasoned. The results of the analysis indicates a usage date for the wood after 1552 [1].

Condition of the painting

Although the portrait had a number of areas where the paint was flaking and vulnerable (Fig. 3), which were consolidated with sturgeon’s glue, it was in good overall condition.

HKI-3097_img-5 — Fig. 3. Detail of lifting and flaking of the paint layer in raking light. (© Polkownik)

The varnish that covered the surface had slightly yellowed, dulling the colours and flattening the fabulous dress full of jewellery worn by the sitter (Fig. 4).

Fig. 4. Detail of the yellow varnish on the jewels (© Polkownik) — Fig. 4. Detail of the jewelled costume covered by yellowed varnish (© Polkownik)

However, one thing really drew the eye: the lime green background . One could see the background looked dubious and was likely to have been overpainted (Fig. 5). Some fake cracks had also been painted in the background around the face, to try and integrate the area better, and the overall surface was cracked, reminding crocodile skin. It was decided with the curators to do some testing and find out if it was possible to remove the overpaint, what was underneath and what condition it was in.

Fig. 6. Detail of the background (© Polkownik)

After close observation under the microscope, we came to the conclusion that most of the surface was covered by overpaint (Fig. 6).

Fig. 5. Diagram showing the overpaint (in red). (© Polkownik) — Fig. 6. Diagram showing the overpaint (in red). (© Polkownik)

Cross-section

A paint sample was taken and set in resin (cross-section). The sample showed the original paint layer (2-3) was covered with two thick layers of overpaint (4-5) and non-original varnishes, tinted (6-7) and untinted (8-9) (Fig. 7).

Conservation Treatment

During testing, it was revealed that the overpaint could easily be removed. Three areas were tested; two showed an original paint layer underneath that appeared in good condition, and one test showed an abraded area. It is a difficult decision to remove such a large area of overpaint based on the three small test patches. But as the cleaning progressed (Fig. 8), it became clear that we were right to do this: the background was in good condition, apart from a small abraded area in the background close to the back of the head of the sitter. It seems astonishing that such a small damage warranted the overpainting of the whole background.

HKI-3097_img-15 — Fig. 8. During cleaning (© Polkownik)

The original background is a dark green/brown, showing variations in opacity and in brush handling. It looks vibrant and lively, and complements the sitter’s red dress and pale rosy carnation.

Fig. 8. After cleaning (© Polkownik) — Fig. 9. After cleaning (© Polkownik)

After the removal, the painting was varnished (Fig. 9), the losses filled (Fig. 10) and retouched (Fig. 11) with reversible materials, and the abraded areas in the background were lightly dotted in. Treating this painting stabilised the materials (through the consolidation of flaking paint) and brought it a step closer to its original 16th-century style.

HKI-3097_img-19 — Fig. 10. After filling (© Polkownik)

Fig. 10. After retouching (© Titmus) — Fig. 11. After retouching (© Titmus)

Camille Polkownik, 2nd year Post-Graduate Intern (2015-2017)

About the Author:

Ms Camille Polkownik graduated with a Master’s Degree in the Conservation and Restoration of Paintings in 2014, from the École nationale supérieure des arts visuels de La Cambre in Brussels (Belgium). She also has a Bachelor degree in the Conservation and Restoration of Painted Works (2011) from the Superior School of Fine Arts, in Avignon (France). She has interned at the Royal Institute for Cultural Heritage (KIK-IRPA, Belgium), the Royal Museums of Fine Art of Brussels (Belgium), the Museum of Fine Arts in Nice (France), the Art Gallery of New South Wales (Sydney, Australia) and in private studios.

Her current research projects include the study of extenders added to Prussian Blue; the quality variations in lead white and how they affect paint properties; and the characterisation of Prismatic Lead White, an unusual form of lead white, through X-ray Diffraction analysis and Polarised Light Microscopy.

To contact Camille: camille.polkownik@gmail.com

[1] Tyers, Ian, Dendrochronological Consultancy Report 907, pp. 1-4.

Tickled Pink: Unexpected Discoveries in the Painting Technique and Treatment History of Pinturicchio’s Virgin and Child

Fig. 1a Pinturicchio, Virgin and Child with Saint John the Baptist, c. 1490-5 before treatment (©Titmus)

Virgin and Child with Saint John the Baptist (Fig. 1a-1b) was brought to the Hamilton Kerr Institute for treatment in the spring of 2016 prior to the painting’s display in the Madonnas and Miracles exhibition. While the painting’s condition was stable when it arrived, the varnish was dull and slightly greyish, and it was decided that varnish removal would provide an aesthetic improvement. Although the treatment was not particularly complex, I found studying the materials and techniques Pinturicchio used in this work and researching the painting’s treatment history to be a rewarding and edifying experience.

Virgin and Child dates to 1490-1495 and was acquired by the Fitzwilliam Museum in 1880. This work is only one of numerous paintings by Pinturicchio of this subject, with two of the most closely related versions in the Ashmolean Museum of Art and Archaeology and the Philadelphia Museum of Art. Variations in the paint handling and quality of these works may be attributed to the involvement of workshop assistants.

Materials and Technique

Pinturicchio painted the Fitzwilliam’s Virgin and Child primarily in egg tempera, enriched with oil glazes and gilding. As was traditional in Italian paintings of this period, the flesh tones are underpainted with a greenish layer termed verdaccio. Additionally, dispersed pigment samples were taken from the Virgin’s robe, and the pigment was identified as high quality coarse azurite using polarized light microscopy. Unfortunately, the robe appears much darker and less three-dimensional than it would have been when first painted. As often occurs with azurite, the paint has discoulored from aged medium and varnish, and the paint layer has suffered abrasion from past restoration treatments. When initially painted, the robe would have been a bright blue and would have appeared to drape more realistically: examination of the painting using infrared reflectography (Fig. 2) revealed extensive underdrawing in a liquid medium, and folds in the robe were both underdrawn and possibly outlined with carbon-containing black paint.

Fig. 2 Infrared reflectogram of Virgin and Child (©Titmus) — Fig. 2 Infrared reflectogram of *Virgin and Child (*©Titmus)

Perhaps the aspect of Pinturicchio’s technique I found most intriguing, however, was his method of underpainting. Microscopic (Fig. 3) and cross-sectional analysis of the paint layers in the Virgin’s robe revealed a locally-applied pink underlayer. John Brealey, the paintings conservator who treated the painting previously, estimated this layer to contain madder – a red lake – although analysis was not undertaken to confirm this identification. This underlayer does not seem to have been modelled to any significant extent, since the radio-opacity in the X-radiograph is quite even.

Fig. 3 Microscopic detail of pink paint showing through the abraded azurite of the Virgin’s robe in Virgin and Child (©Rayner) — Fig. 3 Microscopic detail of pink paint showing through the abraded azurite of the Virgin’s robe in *Virgin and Child* (©Rayner)

The purpose of a pink or red underlayer in the mantle would have been to warm the resulting hue once the blue paint had been applied, as azurite can sometimes appear greenish. As Christine Kimbriel and Youjin Noh explore in “Sebastiano del Piombo’s Adoration of the Shepherds: On the Pursuit of Colouristic Splendour in a ‘Lost’ Painting,” it was not uncommon to find blue over pink or red underlayers in fifteenth-century and early sixteenth-century Venetian painting.1 Kimbriel and Noh cite examples of paintings by Giovanni Bellini, Sebastiano del Piombo, and Giorgione with this type of layering.

In contextualizing Pinturicchio’s use of this type of layering, it became clear that there are extant examples of works containing underpainting of lead white and red lake underneath blue robes or sky from as early as the fourteenth and fifteenth century, including paintings by Giotto.2 Raphael, who came to prominence only a generation after Pinturicchio, is perhaps the best-known example of a central Italian artist using this method.3

Additionally, this type of layering was a common technique in the painting of frescoes. For example, a layer of red ochre underlies azurite pigment in Perugino’s The Circumcision of the Son of Moses in the Sistine Chapel.4

While the presence of this pink layer in Pinturicchio’s Virgin and Child was initially surprising, it became apparent through research that the artist’s technique follows a tradition of employing pink and red underlayers under blue for optical purposes.

Elisabeth Petrina, 1st year student, used the information and reconstructed this painting with historically-accurate materials.

Treatment History

It is not often that documents recording the historic treatment of paintings exist, but when they do, they can afford the opportunity to reflect upon past conservation practices and study how specific restoration materials have aged. This was found to be the case with Virgin and Child, which was previously treated by John Brealey (1925-2002) in 1964. Brealey was a prominent figure in the history of paintings conservation, and his ideas and philosophies have had long-lasting significance for the field. He was a member of the advisory council of the Hamilton Kerr Institute at the time he treated this painting, and he left London in 1975 to become the chairman of paintings conservation at the Metropolitan Museum of Art.

The treatment report and photographs of Virgin and Child indicate that a good deal of previous restoration was removed by Brealey, but some old retouching and gilding was left. In Brealey’s words, “The gold hatching indicating the highlights is bogus, but has been left on because there must have been something similar on originally.” The thinking described in the treatment report is in line with Brealey’s well-known philosophy of selective cleaning. Ultraviolet examination of the painting (Fig. 4) confirmed that retouching from at least two campaigns of restoration were still present: Brealey’s and at least one previous restoration.

Fig. 4 Ultraviolet light photograph of Virgin and Child before treatment showing numerous campaigns of previous restoration (©Rayner) — Fig. 4 Ultraviolet light photograph of *Virgin and Child* before treatment showing numerous campaigns of previous restoration (©Rayner)

Significantly, the report also specifies that the painting was revarnished with MS2A®, MS2B®, and wax. Both of the MS2® varnishes are ketone resins, with MS2B® having a slightly different solubility and higher viscosity.5 The identification of these coatings accorded with their appearance, since synthetic varnishes can have a tendency to grey and dull rather than yellow like natural resin varnishes (Fig. 5). Knowing the materials used to varnish the painting allowed testing of the theory that the coatings should remain easily reversible over time. While they were certainly still soluble, organic solvents of a surprisingly high polarity were required in order to remove the conservation varnish.

Treatment

In spite of the unexpected polarity of the synthetic coating, varnish removal was relatively straightforward except for within the Virgin’s blue robe. The coarse azurite in this area was found to be under-bound. This means there was a higher ratio of pigment to oil, not sufficient to fully coat the particles and bind them into the polymerised oil network. Contrary to the rest of the painting, the robe was cleaned using a quickly evaporating solvent on cotton swabs, lightly rolled over the surface, in order to solubilize and reduce the varnish without excess mechanical action.

Significant amounts of overpaint and chalk fill material had been left covering original paint, so treatment also involved reducing these foreign materials under the microscope (Fig. 6). Additionally, discolored brown material within the halo was reduced using aqueous solutions and gels.

Fig. 6 *Virgin and Child* before retouching (©Titmus)

Unfortunately, I was unable to complete the treatment prior to finishing my post-graduate internship in the summer of 2016. The filling, retouching, and revarnishing were carried out by the Hamilton Kerr Institute’s Director, Rupert Featherstone (Fig. 7).

Fig. 7 Virgin and Child after treatment: Virgin and Child (©Titmus) — Fig. 7 *Virgin and Child* after treatment (©Titmus)

Although I would like to have seen this treatment from start to finish, I learned a great deal from the opportunity to study this artwork. I hope this text provides some insights into the creation and history of the work, and that you will visit the Fitzwilliam Museum to see Virgin and Child for yourself!

Kari Rayner, 2nd year Post-Graduate Intern (2015-2016)

About the Author:

Ms Kari Rayner holds a Master of Arts in Art History and an Advanced Certificate in Art Conservation from New York University, USA. She also graduated with her Bachelor of Arts in Art History, Art Theory and Practice from Northwestern University, USA. During her graduate studies, Kari interned at the Wallraf-Richartz-Museum in Cologne and worked at Modern Art Conservation in New York, NY. Her final-year internship was undertaken at the National Gallery of Art in Washington, D.C., and she completed a year-long post-graduate internship at the Hamilton Kerr Institute from 2015-2016. Kari returned to the NGA in the fall of 2016 as an Andrew W. Mellon Fellow in Paintings Conservation.

To contact Kari: rayner.kari.s@gmail.com

Notes

1 Kimbriel, Christine and Youjin Noh. “Sebastiano del Piombo’s Adoration of the Shepherds: On the Pursuit of Colouristic Splendour in a ‘Lost’ Painting.” In Artists’ Footsteps: The Reconstruction of Pigments and Paintings: Studies in Honour of Renate Woudhuysen-Keller. S.l.: Antique Collectors’ Club, 2013.

2 Sincere thanks to Elizabeth Walmsley of the National Gallery of Art, who shared her expertise in Italian painting and directed me to the following resources on the topic of pink/red underlayers. Borgia, Ilaria, Diego Cauzzi, Bruno Radicati, and Claudio Seccaroni. “Raphael’s Saint Cecelia in Bologna: New Data about its Genesis and Materials.” Raphael’s Painting Technique: Working Practices Before Rome. Proceedings of the Eu-ARTECH workshop. Eds. Ashok Roy and Marika Spring. Page 95

3 Ibid, page 95

4 Santamaria, Ulderico and Fabio Morresi. “Perugino’s technique in the Sistine Chapel: scientific investigations.” The Painting Technique of Pietro Vannucci, called Perugino: Proceedings of the LabS TECH Workshop. Eds. Brunetto Giovanni Brunetti, Claudio Seccaroni, and Antonio Sgamellotti. Pages 99-100

5 “Low Molecular Weight Varnishes.” Ed. Wendy Samet. Paintings Specialty Group Wiki, 1997. Web. Accessed June 4, 2017. http://www.conservation-wiki.com/wiki/IV._Low_Molecular_Weight_Varnishes

Madonna and Child by the Master of the Castello Nativity

In preparation for the Fitzwilliam Museum’s exhibition Madonnas and Miracles: Private Devotion in Renaissance Italy paintings from the Fitzwilliam Museum collection came to the Hamilton Kerr Institute to be restored, including this beautiful and colourful panel of the Madonna and Child by the Master of the Castello Nativity . When the painting arrived at the studio, the two main issues were a discoloured varnish layer and a very visible and irregular retouching covering the joint in the centre of the panel from top to bottom. This was my last project at the HKI; I left before I was able to finish it so Mary Kempski, Senior Paintings Conservator at the Institute, carried out the filling and retouching, bringing the treatment to completion.

Before treatment (© Titmus) — Before treatment ( Titmus)

The artist

Little is known about The Master of the Castello Nativity. He was an Italian painter, active in Florence and Prato in the mid-15^th century, as well as a follower and possible pupil or collaborator of Filippo Lippi (c. 1406-69). He was nicknamed after another of his paintings of the Virgin adoring the Christ Child which originally came from Castello and is now kept in Florence [1] Around 30 paintings have been ascribed to him, a few of them show the same composition, as can be seen in the versions in the Uffizi, Florence and in the Huntington Library, California. All three versions have similar features: the kneeling Virgin praying with the Child in front, the star on the Virgin’s shoulder (probably Stella Maris), the veils covering the head and the hands of the Virgin, the gold decoration of the robes, the vegetation and the golden rays around the baby. The three paintings are of a considerable size and the one from the Fitzwilliam is the smallest.

The panel

The wooden panel (86.7 cm x 59.4 cm x 3.4 cm), most likely poplar, consists of two boards with the grain running vertically. At the back, the surface is irregular and shows tool marks from the initial preparation of the panel. The woodworm damage in the central section is severe and may well have weakened the panel internally causing it to split, a damage now visible from the front. The visible open channels from the woodworm activity on the vertical edges of the panel indicate that the edges have been cut off and the general size reduced at some point. The presence of six rectangular holes on the back could be related to a previous use of the panel, although their function is currently unknown.

The X-ray examination revealed the presence of an original piece of canvas covering the joint top to bottom and located under the ground and paint layers. It was common practice at this period to cover the defects and joints of the support with canvas soaked in glue before applying the ground layer. This would help level the surface and strengthen the weakest areas. Curiously, the canvas is missing just at the very bottom of the painting, but the reason for this is so far unknown.

The painting technique

The paint was in good condition, apart from extensive retouching along the split, as well as in the bottom corners. Based on the appearance and handling of the paint, the figures are most likely painted with tempera, while the landscape appears to be done in oil. The detailed areas of vegetation display very thick impasto. Upon ageing, the oil layers have become more transparent, allowing the previous layers of oil underneath to be seen, as is the case in the roses and the trees.

The gold, probably water-gilded, has been re-gilded in some areas. To recreate the volume of the curtain of the pavilion, dark glazes have been applied to the gold drapery, and some engraved marks (scoring and punching) were applied to give the gold different textural reflections.

The treatment

The work started with a full optical examination. Ultraviolet light revealed a discoloured varnish layer (probably a natural resin as it fluoresces in UV light, although not strongly) and a discoloured and irregular retouching covering the joint.

Joint before treatment (© González Juste) — Joint during treatment ( González Juste)

Joint during treatment ( González Juste)

The painting was surface cleaned and the varnish removed. After removal of the top varnish layer, it was evident that there was still another varnish on the surface, in particular on the blue of the robe and the greens of the background. A stronger solution was used in order to remove the last remnants of the varnish. The removal of the varnish layer also involved the removal of the majority of the overpaint, although there were remnants on the joint of the boards in the bottom right corner, and some across the red robe. These remnants were tough and probably older than the rest, possibly in a different medium.

During varnish removal under UV (© González Juste)

The removal of old fills from the central join revealed at least three campaigns of filling and retouching, covering areas of the original, which had caused bulkiness across the join. The removal of the fills recovered hidden areas of original paint, which were in good condition.

Due to the uneven and dull quality of the flesh tones and the blue and red robes after varnish removal, these areas were examined more closely and samples were taken to try and identify the nature of this top grey layer. The study of the cross-sections suggests that the grey layer mainly consisted of an aged natural resin, too oxidised to lift off with free solvents.

The sample shows that the remaining varnish layer extended into a crack in the underlying original glaze, confirming that it was not original. The cross-section displayed below is a sample from the red robe after initial varnish removal. It shows the ground layer, probably gypsum with some black particles (1), a white pinkish imprimatura with a big red particle (2), a red glaze (3), and the varnish layer (4).

Cross-section from the red robe after initial varnish removal. (©González Juste) — Cross-section from the red robe after initial varnish removal. (González Juste)

After several tests, it was decided that the painting could be greatly improved by removing this layer. As a result, this revealed brighter colours, such as the astonishing ultramarine blue robe and the delicacy of the veil covering the hands of the Virgin.

During dirt removal (© González Juste) — During dirt removal ( González Juste)

After full cleaning (© González Juste) — After full cleaning, before restoration ( González Juste)

After full cleaning, before restoration ( González Juste)

The painting was brush-varnished and the losses were filled and retouched, and the area of damaged gilding in the halo was re-gilded.

After treatment (© Titmus) — After treatment ( Titmus)

Carlos González Juste, 2^ndyear intern (2014-2016)

About the author

Carlos González Juste has a B.A. in History from the Complutense University in Madrid and a Degree in Conservation and Restoration of Cultural Heritage from the Escuela Superior de Conservación y Restauración de Bienes Culturales in Madrid. He has been an intern in the Museo Nacional del Prado (Madrid), other Spanish institutions and the Hamilton Kerr Institute, Cambridge. He has participated in some traditional pigment making projects (“Cuttings: Mindful Hands. Masterpieces of Illumination” by Factum Arte among other projects). He is currently completing his Masters degree in the Escuela Superior de Conservación y Restauración de Bienes Culturales in Madrid and working as a private conservator.

To contact Carlos González Juste: cgjuste@gmail.com

Madonna and Child, by Pietro da Orvieto

This 14^thcentury Madonna and Child belongs to the Fitzwilliam Museum and is attributed to Pietro da Orvieto (1430-84). The painting came to the Hamilton Kerr Institute conservation studio in preparation for the Museum’s exhibition Madonnas and Miracles, which runs until 4^th June 2017.

Condition of the Painting

While the painting was structurally sound, disfiguring and discoloured old retouchings were widespread across the paint surface, most prominent in the necks of the Virgin and Christ. The gilded frame and gilded background also presented a considerable amount of wear and abrasion, revealing the red bole and, in places, the underlying white gesso ground. When looking at the dark blue/black mantle of the Virgin in raking light, it was evident that considerable damage had occurred to this paint passage. The natural resin varnish layer had discoloured and the painting presented a dull greyish tone as the result of surface dirt accumulation and possibly the remains of a glair layer (an egg white varnish). During the treatment of this small painting interesting discoveries were made, such as the beautifully painted reverse, which we will share in this article.

How is the painting made?

This painting has been reconstructed by Anna Don, first year student at the Hamilton Kerr Institute. Her comprehensive step-by-step description includes many impressive photos, offering details that you might otherwise not see.

The support and frame

The painting is on a wooden panel (wood not identified) and is likely to be have been painted using egg tempera and oil glazes, mixed with dry pigments. The reverse of the painting was also painted using egg tempera, but with the exclusion of oil. The background of the painting is gilded, as are some of the details used for the Madonna’s robes. Its integral gilded frame is still present, attached to the front of the panel using nails, as can be seen in the X-radiograph image below. This is a rare find as frames of this type are often discarded having suffered too much damage over time through handling.

Paint layers

A white ground layer, probably of animal glue and gesso (untested) was applied to the back and front of the painting, as well as the frame. The infrared reflectography (IRR) image (see below) revealed the presence of underdrawing in certain areas of the composition, executed in a liquid medium using a brush. Around the figures, it is possible to make out incised lines etched into the gesso to indicate the areas that were to be gilded. The background and haloes are water-gilded in a conventional fashion and display a highly burnished appearance, whilst the decoration of the draperies was done using a mordant gilding technique. The haloes of the two figures were incised with fine circular lines with the use of a compass, while the decorations were made using punch tools.

HKI-3059_img-3 — Infrared (IRR) (© Titmus)

The flesh tones are distinctively Italian in terms of their build-up. The initial modelling was done using a green underpaint layer, known as verdaccio, which is traditionally made using a green earth pigment, as can be seen in the image of the Child below. This was followed by the application of the flesh tones. This layer was applied in fine, repetitive hatched brushstrokes, which is a common feature associated with the use of egg tempera.

The cleaning of the painting was carried out in several stages. The yellowed varnish, which extended from the painting onto the gilded background, as well as the old discoloured retouchings were removed. The upper image shows cleaning tests in the lower left corner, located in the Virgin’s headdress. This instantly made it easier to appreciate the original technique of the painting. It was then possible to remove an additional layer of grey dirt from the gilded background and from the frame mouldings, allowing the beautiful gilded background to shine brightly again.

A sample from the Virgin’s dark blue robe shows a build-up of two paint layers consisting of a greenish blue under layer with a darker, more intense blue upper layer, consisting of coarser pigment particles of azurite.

Sample from the dress, showing coarse azurite particles (© van Dorst)

The reverse

The painting’s biggest secret was revealed when the reverse was cleaned to uncover a colourful and decorative marble or porphyry imitation scheme, which is framed in a trompe-l’oeil stone moulding. This is a decorative motif commonly found in small scale, early Italian panel painting, but has been observed on a work by Albrecht Dürer. The painting on the reverse was completely obscured by the thick layer of dirt. To facilitate the painting of the straight lines that make up the grey borders, the artist incised the lines in the ground layer. The bright and fantastic colours of the reverse of this small devotional panel can once again be seen and admired.

Varnishing and retouching

It was decided to apply a protective and re-saturating varnish layer only to the painted areas on the front of the painting, but not to the gilded background, the gilded frame or to the reverse of the painting. This approach is in keeping with early Italian painting practice where the gilded areas, especially the water gilding, would have been left unvarnished. However, the painted areas on the front required a varnish layer in order to re-gain their saturation, whilst also providing an isolating layer between the original paint and the subsequent retouching.

The losses in the painted areas were toned with watercolour and glazed with Gamblin Conservation Colours. In the gilded areas, the losses were toned in a red colour, slightly lighter than the colour of the original bole.

Conclusion, come and see!

Written by Camille Polkownik and Sarah Bayliss, conservation treatment by Sven van Dorst.

About the author:

Sven Van Dorst graduated magna cum laude at the Artesis University College Antwerp (Belgium) in 2012, majoring in paintings conservation and restoration. The following two years, he worked on several projects at the Royal Museum of Fine Arts Antwerp and as a freelance conservator and painter. Sven completed a two-year postgraduate internship at the Hamilton Kerr Institute in 2016 and is currently working at The Phoebus Foundation (Belgium) as a conservator and researcher. Recently, he published essays on the technique of Antwerp flower painters in the Hamilton Kerr Bulletin and the Power Flower exhibition catalogue (Rockoxhuis Museum) as well as a piece on the 20^th century Belgian artist Gustave van de Woestyne (catalogue: “Rooted, Painting Flanders”). In 2018, Sven will commence the treatment and research of the Dymphna altarpiece by Goswijn van der Weyden.

To contact Sven: sven.vandorst@phoebusfoundation.org

Uncovering vibrant colours through cleaning

Virgin and Child by Jos van Cleve is an oil painting on a wood panel that belongs to the Fitzwilliam Museum, Cambridge. The work was recently restored in preparation for the upcoming exhibition Madonnas and Miracles. The painting was in excellent condition prior to the conservation treatment, apart from a discoloured varnish that obscured the surface and dulled the vibrant colours used by the artist.

The Artist

Joos van Cleve (1464-1540) was a German-born painter active in Antwerp during the first half of the 16th century. His style can be described as a mixture of traditional Flemish and Italian Renaissance techniques. This particular painting, created between 1525-1529, is a good example of his hybrid style, as the traditional Flemish paint build-up and landscape contrasts with the Virgin’s sfumato shadows copied from paintings by Leonardo da Vinci. The subject of the Virgin and Child was very popular during this period and numerous versions of this composition exist by Joos van Cleve and his studio. The Fitzwilliam version has a peculiar detail, namely that the Virgin is smiling and her teeth are visible between her lips; a feature not usually seen in other representations of the subject.

Before treatment, normal light, front (© Titmus)

Close up of the face of the Virgin (© Polkownik)

Joos van Cleve, The Holy Family (Currier Museum in Manchester, New Hampshire )

(click to enlarge photos)

The painting: construction and layers

The wooden support consists of two oak boards, quarter sawn and butt-joined using animal glue. The boards have not separated since the panel’s creation, demonstrating the high quality of the wood and the expertise of the panel makers. We know that the panel had an original engaged frame, since a raised edge or ‘barb’ can be seen along the edge of the white chalk ground. This indicates that the panel was inserted into a frame immediately after its construction. Following this, the ground layer would have been added to the panel and the front of the frame simultaneously, leaving a build-up of ground along the inside of the frame.

Barbs of ground and paint layer indicating the painting was painted in its engaged frame (© Polkownik)

A Flemish panel painting of this period would typically have been sized with a layer of animal glue on both sides, in order to limit the hygroscopic response of the wood. Following this, a ground layer would have been applied to the front of the panel in 1-2 layers and sanded to obtain a smooth finish. Northern grounds from the 15th-16th centuries are characterised by their use of animal glue and chalk (calcium carbonate), in contrast to the gypsum (calcium sulphate) grounds used by Italian artists during this period. The preparation of the ground was most likely carried out by professional panel makers, as opposed to the artist’s own workshop. Upon receiving the prepared panel, the artist would start by isolating the ground with a layer of oil (usually linseed or walnut). An initial design of the composition would then be drawn on top of the ground using a dry medium such as charcoal, pencil or chalk. In other cases wet media such as ink or diluted paint were used.

These preparatory designs or ‘underdrawings’ are often obscured entirely by subsequent applications of paint and are therefore invisible to the naked eye. However, the carbon content of traditional underdrawing media ensures that they can be seen using infrared reflectography; an imaging technique that makes use of the longer wavelengths of infrared radiation to penetrate the upper paint layers and reveal the drawing below (Fig.). This method was used to uncover the detailed underdrawing used for the Fitzwilliam painting. Through scrutinising the intricate draughtsmanship that provided the basis for the composition Joos van Cleve’s mastery is fully revealed. A variety of lines were used to create an initial sketch for the composition, ranging from the curved outlines of the infant Christ’s flesh to the more angular and hatched marks used to indicate the folds of the Virgin’s robe. In contrast to the detailed design reserved for the figures and drapery, there appears to be no underdrawing present for the landscape. It is possible Joos van Cleve had an apprentice in his workshop who filled in this part of the composition without the use of a preparatory design, as it was common to have students and trainees specialise in painting various parts of the painting.

Once the underdrawing was complete the paint was applied using very thin layers. The darker passages of the painting consist of several transparent layers painted on top of each other to give depth, exemplified by the folds of the Virgin’s robe and the darker tones of the landscape. Finally, the painting would have been finished through the application of a varnish, which most likely consisted of a natural resin dissolved in spirit or cooked in oil. The purpose of a varnish is to saturate the colours within the painting, creating a sense of depth, whilst also harmonising the various tones throughout the composition.

Detail of the background, left side. The shadows are made of multiple transparent layers, which gives depth to the composition (© Polkownik)

Conservation treatment

The initial treatment step consisted of surface cleaning to remove the thin layer of dust and grime that had accumulated on the painting’s surface over time. The varnish was then removed using organic solvents, which were chosen based on previous cleaning tests. The yellowed appearance of the varnish had a flattening effect on the shapes within the composition, whilst also dulling the vibrancy of the colours. The removal of the varnish revealed a significant visual improvement for the painting. However, this was only the beginning. Underneath the varnish a grey layer of dirt continued to obscure the colours within the composition and its removal brought even more luminosity to the surface of the painting. In addition, a campaign of overpaint covered passages of old abrasions and losses, most notably in the red cloak of the Virgin and the tree on the right-hand side of the painting (these passages of overpaint are marked using red in the lower right photograph).

Detail during varnish removal (© Polkownik)

Cleaning test in the upper left corner: removing the grime present under the varnish (© Polkownik)

After the removal of the final dirt layer a very old, degraded layer of varnish remained on the cloth of honour behind the Virgin. It is possible that this localised coating was left by a previous restorer, perhaps due to the sensitivity of the paint in this area to organic solvents. The cloth, originally blue, had acquired a brownish-grey tint. Microscopic samples were taken from the painting to establish whether this layer was original or not. Examination of the samples in cross section indicated that the grey layer consisted of an old, oxidised varnish, as opposed to a pigment-containing glaze. The cross section samples further showed that the layer underneath contained blue and red pigment particles, creating an optical purple colour (see below). However, after cleaning the colour revealed showed a slightly more blue hue, most likely due to the photo-degradation and resultant fading of the organic red lake used for the optical mixture.

3075nl — Sample from the cloth of honour, normal light (Polkownik)

Sample from the cloth of honour, normal light (Polkownik)

3075-1b — Sample from the cloth of honour, ultraviolet light (Polkownik)

Sample from the cloth of honour, ultraviolet light (Polkownik)

Once it was clear that the uppermost degraded varnish layer was not pigmented, and therefore not considered original, we proceeded with the removal of this layer. The picture below shows the right side of the cloth after cleaning, revealing a vibrant purplish blue, while the left side is still covered by the discoloured varnish.

HKI-3075_img-45 — Fig. During cleaning, the right half of the cloth of honour has been cleaned ( Polkownik)

Fig. During cleaning, the right half of the cloth of honour has been cleaned ( Polkownik)

After the cleaning was complete, the painting was re-varnished using a modern synthetic resin that will not yellow upon ageing. The losses were filled using a water-soluble putty consisting of gelatin and chalk, and the fills were retouched using synthetic resin and pigments. All of the phases of the restoration, including varnish, fills and retouching are designed to be completely reversible, to facilitate their easy removal in the future.

(Click to enlarge photos)

Although this painting came to the Hamilton Kerr Institute for minor restoration in preparation for an exhibition, the treatment served the purpose of uncovering the hidden brightness of the colours, whilst also bringing forth the previously flattened volumes and shapes within the composition, most notably in the delicate sfumato of the Virgin’s face. The opportunity to restore such a beautiful and exceptionally well preserved painting was extremely enjoyable, whilst observing the mastery of Joos van Cleve in such detail helped broaden my understanding of 15th century Flemish painting technique.

Camille Polkownik – 2^nd year Post Graduate Intern (2015-2017)

The Madonnas and Miracles exhibition (video)

About the Author

Ms Camille Polkownik graduated with a Master’s Degree in the Conservation and Restoration of Paintings in 2014, from the École nationale supérieure des arts visuels de La Cambre in Brussels (Belgium). She also has a Bachelor degree in the Conservation and Restoration of Painted Works (2011) from the Superior School of Fine Arts, in Avignon (France). She has interned in the Royal Institute for Cultural Heritage (KIK-IRPA, Belgium), the Royal Museums of Fine Art of Brussels (Belgium), the Museum of Fine Arts in Nice (France), at the Art Gallery of New South Wales (Sydney, Australia) and in private studios.

Her current research projects include the study of extenders added to Prussian Blue from 18th to 20th century in Europe, while matching and comparing paint samples to historic sources, and the characterisation of an unusual form of lead white called “Prismatic Lead White”.

To contact Camille Polkownik: camille.polkownik@gmail.com

In-situ at Deene Park, Northamptonshire

Back view of Deene Park at the end of day. (© Polkownik)

On April 27^th 2016, Carlos Gonzalez Juste (2^nd year post-grad intern), Mary Kempski (supervisor and senior conservator) and myself travelled to Deene Park, between Corby and Stamford (Northamptonshire), to take care of 12 paintings that have suffered from mould and record their profiles in order to monitor changes to their panel support curvatures.

The entrance of the Courtyard. (© Polkownik)

Deene House is a sixteenth century property incorporating a medieval manor and has been occupied by the Brudenell family since 1514 up until this day. The house has a grand style, with many paintings of ancestors as well as family heirlooms. As this house is lived in and not a museum, no photos of its interior will be published, only details of the paintings and the work done on them.

The twelve paintings are family portraits dating back from the seventeenth century. They are painted on oak panels by a British artist/studio and represent children and women at various ages. It is not known who they are but it seems likely they were members of the Brudenell family.

Detail of one of the family portraits. (© Polkownik)

The paintings had suffered from humidity and had developed mould on the reverse of the panels. Not all panels were affected: some of them had been restored in 1966, and the reverse had been impregnated with a mixture of wax and resin, which acted as a barrier. The restored panels were thus protected from mould. However, this wax mixture also acted as moisture barrier, and these panels were less affected by the recent lowering of relative humidity in the house, which caused the more sensitive panels to warp and adopt a more pronounced curvature.

The paintings with whitish reverse are coated with wax. (© Polkownik)

This in-situ had three objectives: remove the mould, take the curvature of the panels for monitoring and future comparison, and reframe the paintings to a conservation standard.

The paintings were first taken off the walls. All 12 could not be taken off at once since the space was restricted, which meant we could only work on 4 to 5 paintings at the same. As soon as one was done, it was put back on the wall and another one was brought in.

The mould was first removed using swabs and alcohol (click on photos to enlarge).

Mould on the reverse on one of the panel. (© Polkownik)

Polkownik removing the mould by swabbing it with IDA. (© Polkownik)

Swabbing the mould with IDA. (© Polkownik)

This enabled us to then unframe the paintings. A few of them had been restored by the Hamilton Kerr Institute several years before and already had proper framing. The rest were improperly framed, with nails holding the panels in their frames which were restricting their movements and could cause internal stresses. Luckily, no splits had developed or joints opened.

Unmounting the paintings from the wall. (© Polkownik)

Unmounting the paintings from the wall is not always easy with the house decorations. (© Polkownik)

Once the paintings were out of their frames, the curvature profiles were taken on a piece of cardboard, and the current relative humidity and temperature of the room were written down. This will allow us to compare the curvatures at our next visit and understand the sensitivity of the wood to environmental conditions. Charlotte Brudenell (wife of the present owner of Deene Park) is very committed to giving the paintings the best possible conditions in their setting and is hoping to improve the climate control for the panels and all the paintings in the house.

González Juste and Kempski taking the curvature profiles for future reference. (© Polkownik)

The frames that had not been recently restored had their rebates lined with acid-free paper and cork spacers to accommodate the panels. Once the paintings were laid down in their frames, they were kept in place with brass strips at the middle of the top and bottom edges, so as to enable the panels to still move across the grain according to the relative humidity fluctuations. The paintings were then hung back on the wall.

González Juste and Kempski lining the rebate of a frame. (© Polkownik)

Polkownik framing a panel. (© Polkownik)

This in-situ was a very good learning experience, as treating 12 paintings in a day was a great challenge, even with three people. It is interesting to see how one improves as the day wears on and how organisation evolves in order to be as economical as possible. Doing repetitive tasks, such as lining rebates and framing, greatly improves one’s skills and efficiency. The size of the artworks, as well as their location in the rooms and proximity to furniture, also required constant teamwork in order to move and re-hang them safely. The Hamilton Kerr Institute will soon return to Deene Park to continue the monitoring and preventive conservation of its artefacts.

Camille Polkownik – 1^st year Post-Graduate Intern at the Hamilton Kerr Institute (2015-2017)

About the Author

Ms Camille Polkownik graduated with a Master Degree in the Conservation and Restoration of Paintings in 2014, from the École nationale supérieure des arts visuels de La Cambre in Brussels . She also has a Bachelor degree in the Conservation and Restoration of Painted Works (2011) from the Superior School of Fine Arts, in Avignon, France. She has interned in the Royal Institute for Culture Heritage (KIK-IRPA, Belgium), the Museum of Fine Arts in Nice (France), in private studios and at the Art Gallery of New South Wales (Sydney, Australia).

To contact Camille Polkownik: camille.polkownik@gmail.com

Review of 2016 ENCoRE Conference, Cambridge

ENCORE Conference, held at Wolfson College, Cambridge. (© 2016 Polkownik)

ENCoRE is a network organisation of European higher education institutions operating in the field of conservation-restoration. It was founded in 1997 with the principal objective to promote and develop research and education in the conservation of cultural heritage. The conference held in Cambridge on April 13^th 2016 was entitled “ENCoRE: On Practice in Conservation-Restoration Education”. Two more days followed, called General Assembly, where the different actors talked about the current issues in conservation education.

As the title says, education is a major focal point of ENCoRE. Another important point that was raised that day was the importance of research and its relationship to education. In many other fields, it is easy to imagine these two linked. But for us conservators, linking lab research to studio practice is not always easy.

A short summary of each talk follows:

Rupert Featherstone giving the opening speech. (© 2016 Polkownik)

Sebastian Dobrusskin. (© 2016 Polkownik)

Key-note speaker René Larssen, associate professor at the Royal Danish Academy of Fine Arts in Copenhagen, stressed in his presentation the importance of doing research consistently, in small practical projects. Through two case studies, he showed how simple observations of alterations can be translated into hypotheses that can then be investigated by researchers and scientists. In short, early and systematic communication between conservators and researchers leads to a faster problem solving and thus a better understanding of the aging of our treatments on works of art. Another very important point he raised was the need to adopt standardized terms through the European Committee for Standardization (CEN), an idea that was backed up by Leslie Carlyle during the Q&A. She illustrated her argument with the need for standardisation of UV filters so that photos of artworks and cross sections can be compared between institutions.

Sebastian Dobrusskin, Professor for Conservation and Restoration of Graphic Art and Photography at Bern University of the Arts, described the structure of the conservation programme at his university and mentioned the difficulties of communication related to the three national languages of Switzerland: German, French and Italian, as well as new research programs more adapted to students needs.

Alison Heritage and Chaiman Wolfgang Baatz. (© 2016 Polkownik)

Douwtje van der Meulen, (© 2016 Polkownik)

Silvia García Fernández-Villa, (© 2016 Polkownik)

Elisabeth Peacock, Professor at the University of Gothenburg, explained how she designed a Research Methods Course from scratch, after receiving complaints from students feeling unprepared for independent research. After attending an ICOM Summer Course in 2013, in four months she designed a structured course oriented towards problem-solving learning formats, so students can become familiar with research methods while benefitting from collaboration with students from different backgrounds and levels of ability.

Alison Heritage, ICCROM, talked about the importance of educators in promoting research. Heritage science creates cultural values and links various fields together, and in her opinion, collaboration is the key element to success as a discipline. She also acknowledges that teamwork can be challenging due to lack of trust between individuals with vast differences in personalities or culture.

Like Peacock, Lecturer in Conservation at the University of Oslo Douwtje van der Meulen put together a course package and worked with students to improve it. The course was centred around general skills such as problem solving and critical thinking, basic research skills and communication. Her teaching philosophy is called “active learning” as inspired by Confucius’ quote: “Tell me and I will forget, show me and I will learn, involve me and I will understand.” By teaching students how to gain knowledge through research, then discussing their results and using their findings in an essay, she noticed that the information was better assimilated since the students could see how to use it in their practice.

Key-note speaker Leslie Carlyle, currently Professor at the University of Lisbon presented case studies demonstrating the gap between the information available in conservation and the practice. She notably pointed out how long it takes for practices to be properly studied and written about, choosing the example of the nylon coating (used on everything and anything since it was so popular in the 1960’s) and diammonium citrate for the cleaning of paintings. She also demonstrated the passage of time between the publication of literature and its assimilation into practice. In a case study, she spoke of conservators ignoring the literature or not having access to it, and choosing to use products that were no longer recommended, creating long-lasting conservation issues for objects. Finally, she mentioned the latest conference on Lead Soaps, held in March 2016 at the Rijksmuseum. This conference was, in her opinion, the first one where conservators and scientists fully collaborated in order to get a better understanding of this degradation phenomenon and to find solutions to the problems created by these soaps. As conservators are doing more and more research, they elevate themselves to the level of scientists, which helps them better formulate questions to get faster answers.

Boris Kvasnica, Professor at the Academy of Fine Arts and Design in Bratislava, explained the structure of the conservation programme and the importance of collaboration between different fields, illustrating his point with case studies of students in conservation, chemistry and art history successfully working together.

Finally, the last speaker was Silvia García Fernández-Villa, associate professor at the University of Madrid, stressed the importance of including students in research projects to help them get familiar with specific materials and analysis methods used in conservation science. She used, as an example, projects past and ongoing dealing with synthetic polymers and their ageing. Not only were the students improving their knowledge in chemistry and science, they could apply this newfound knowledge to practical cases, notably contemporary artworks.

Panel discussion at the end of the day. (© 2016 Polkownik)

The talks ended with a panel discussion, which raised questions like “what is conservation research” or “how much should research be stressed in the conservation-restoration curriculum?” but these questions will not be discussed in length in this article. Participants then enjoyed a glass of wine while gathering around the posters designed by students.

In conclusion, this conference, although oriented towards teachers and how to make their courses better, was very interesting for students and young graduates. This forum showed that teachers are constantly trying to improve conservation-restoration coursework, despite little means, little time and heavy responsibilities and expectations from schools and universities.

Camille Polkownik – 1^st year Post Graduate Intern at the Hamilton Kerr Institute

Coffee break is mingling time. (© 2016 Polkownik)

Coffee break in the sun. (© 2016 Polkownik)

Rayner putting up students posters. (© 2016 Polkownik)

Clarke and Straub case study posters. (© 2016 Polkownik)

The students posters will be soon posted on CeROArt (the link will be added as soon as it becomes available).

To contact Camille Polkownik : camille.polkownik@gmail.com

In Situ at Middle Temple, London

Summary of our in situ at Middle Temple, London, 26-30/10/2015

garden-panorama — Panorama of Middle Temple (© Middle Temple)

From the 26th to the 30th of October 2015, Amiel Clarke (2^nd year student), Kari Rayner (1^st year Post Graduate Intern), Sarah Bayliss (1^st year Post Graduate Intern) and myself (1^st year Post Graduate Intern) accompanied Senior Painting Conservator Mary Kempski to Middle Temple in London (http://www.middletemple.org.uk/).

Middle Temple is one of the four Inns of Court which have the exclusive right to call students to the Bar. One of Middle Temple’s main functions now is to provide education and support for new members to the profession. It is also a professional society with international members. Middle Temple is located in the wider Temple area of London, near the Royal Courts of Justice. One of their core purposes is the maintenance of the Inn’s estate and its historic heritage: this is where we painting conservators come in.

We were called to treat paintings with various damages, such as small tears, scratches in the varnish or matt spots, and the accumulation of heavy grime. The specific setting at Middle Temple presented additional complications and required problem solving as a team.

The work was done on site, as the paintings needed minor treatments. The challenge was twofold: conserving 7 paintings, mostly portraits, in four days and doing so in a restricted space. This meant collaborating with each other at all times, as some of the paintings were large and could not be moved single-handedly. The configuration of the room also had to be modified numerous times in order to swap the artworks around and allow framing on the tables.

This on-site job was beneficial for both student and interns, as it taught us to work closely with each other. Repeating the treatments on the frames helped us get better and faster at framing: lining the rebate with both brown paper and felt, measuring and cutting balsa spacers to prevent the painting from slipping in the frame, applying soft backboards made out of Tyvek…Having the chance to work in such a secret and beautiful environment is always a benefit, especially when areas are not open to the public and we would not have had the occasion to visit Middle Temple otherwise. We would like to thank Lesley Whitelaw, Senior Archivist at Middle Temple, for making our stay so enjoyable, and will now let the photos speak for themselves.

Camille Polkownik – 1^st year Post Graduate Intern at the Hamilton Kerr Institute

Clarke and Rayner dust vacuuming the back of paintings to remove the debris stuck between the stretcher and the canvas. (© 2015 Camille Polkownik)

Rayner and Clarke surface cleaning a painting. (© 2015 Camille Polkownik)

Dent and tear in the canvas. (© 2015 Camille Polkownik)

After mending the tear, it was left under weights overnight to remove the distortion. (© 2015 Camille Polkownik)

The rabbet is detached from the main structure of the frame. (© 2015 Camille Polkownik)

Gluing the rabbet to the frame using PVA and clamps. (© 2015 Camille Polkownik)

Polkownik consolidating a frame. (© 2015 Amiel Clarke)

The rabbet of the frame after consolidation and proper lining with brown paper and felt. (© 2015 Camille Polkownik)

Sculpting spacers and attaching them to the rabbet of the frame with brown paper. Polkownik consolidating a frame. (© 2015 Camille Polkownik)

Drilling the wooden keys. (© 2015 Camille Polkownik)

Tying the keys to the stretcher to secure the tension. (© 2015 Camille Polkownik)

Proper conservation framing using brass strips and felt tape. (© 2015 Camille Polkownik)

Tyvek backboard stapled through cotton cloth and onto the back of the frame. (© 2015 Camille Polkownik)

Kempski retouching the filled losses on a paintings. (© 2015 Camille Polkownik)

Kempski brush varnishing a painting with Regalrez 1094. (© 2015 Camille Polkownik)

Rayner retouching the losses of the frame. (© 2015 Camille Polkownik)

To contact Camille Polkownik : camille.polkownik@gmail.com

Workshop: The Cleaning of Acrylic Paintings

Course Leader: Bronwyn Ormsby, Principal Conservation Scientist at Tate, United Kingdom.

This two day workshop on the Cleaning of Acrylic Paintings took place in December 2015 at the Hamilton Kerr Institute (Cambridge, UK). The workshop was aimed at conservators with an interest in acrylics but not necessarily experienced with this modern material. The morning sessions were dedicated to the history of modern paints and theory of cleaning while the afternoons were more hands-on.

During these two afternoons, we tested and rated various products used for the cleaning of modern and contemporary artworks. The much-anticipated micro-emulsions, developed in collaboration with the Dow Chemical Company, were made in situ by Ormsby. They offer new possibilities for the cleaning of modern paint layers; although, when we tested them on naturally aged and artificially soiled acrylic samples, there was a natural aura of uncertainty. Depending on the solutions, some did not remove enough of the soiling, and other options worked a little too well, where some pigment was removed with the grime layer. Ormsby suggested it was possible some pigments were not locked into the film upon drying and that as a result, there could be some loose pigment on the paint surface, hence the sensitivity to the slightest mechanical action, which underlines the importance of the application of cleaning products onto these paint layers. Also, some colours were more sensitive than others, like the synthetic organic red paint tested (PV19); the response was also quite dependent on the brand of the acrylic paint used. A lot of information to assimilate for us conservators of Old Masters!

This workshop was a real eye-opener, in the sense that despite knowing these modern paints are difficult and breed new conservation issues, having the chance to actually test many cleaning products on “safe” samples taught us a lot without the risks and consequences of experimenting on real artworks.

A poll was done at the end of the workshop to underline which solutions worked best, and which did not. It was interesting to see that once again, the results were not black and white. Two conservators with the same samples had different results, probably due to handling and application technique. Nevertheless, Ormsby recorded the results in order to understand which systems and micro emulsions worked best overall, to keep improving them for studio use. Ormsby was very down to earth and calm as well as encouraging. No, we do not understand all the problems yet and certainly don’t have all the solutions, but we are progressing towards a better understanding of the risks associated with modern paints, and the research feeding into the development of improved cleaning materials and studio practice.

Camille Polkownik – 1^st year Post Graduate Intern at the Hamilton Kerr Institute

Taking pH readings. (© 2015 Camille Polkownik)

Cleaning the artificial soiling layer. (© 2015 Camille Polkownik)

Carefully taking notes on the effectiveness of the cleaning solutions. (© 2015 Camille Polkownik)

Impressive cleaning on a yellow sample of acrylic paint. (© 2015 Camille Polkownik)

Participants: Bayliss, Rayner, Gonzales Juste, Patrick. (© 2015 Camille Polkownik)

Participants: Straub, Kimbriel, van Dorst, Kempski, Tavares da Silva, Featherstone, Clarke. (© 2015 Camille Polkownik)

Ms Camille Polkownik graduated with a Master Degree in the Conservation and Restoration of Paintings in 2014, from the École nationale supérieure des arts visuels de La Cambre in Brussels . She also has a Bachelor degree in the Conservation and Restoration of Painted Works (2011) from the Superior School of Fine Arts, in Avignon, France. She has interned at the Royal Institute for Culture Heritage (KIK-IRPA, Beligum), the Museum of Fine Arts of Nice (France), in private studios and at the Art Gallery of New South Wales (Sydney, Australia).

To contact Camille Polkownik : camille.polkownik@gmail.com

Conservation of rare books

For more stories from the other conservation departments at the Fitzwilliam Museum, visit the Conservation and Collections Care blog!

Makiko Tsunoda was Icon intern in Manuscript and Rare Book Conservation, sponsored by the Sumitomo Foundation, until April 2013.

Welcome to the conservation students’ and interns’ blog! The primary aim of my internship is to conserve rare books and manuscripts held in the Founder’s Library of the Fitzwilliam Museum. This is taking up the majority of my time, and allows me to expand my skills and knowledge regarding condition assessment, planning, and book conservation treatments.

The Founder's Library in the Fitzwilliam Museum (left); and some of the rare books I have been conserving (right) — The Founder’s Library in the Fitzwilliam Museum (left); and some of the rare books I have been conserving (right)

Continue reading “Conservation of rare books”