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Hannah JonesJanuary 29, 2014AH 103E, Dr. David A ScottAssignment One

A Study of Craquelure at the Hammer

What follows is a case study of the craquelure found on paintings on display at the

Hammer Museum. Paintings were chosen from the Hammer's permanent collection for the

visibility of their craquelure and ease of photographing those effects. Craquelure are cracks and

crevices that form in the layers of paint, size, lacquer, and/or varnish during chemical or physical

processes as a painting ages (Zilberglyt n.d.). The exact cause of a craquelure network is

difficult to pinpoint because of the chemical complexity of these layers and the many factors that

contribute to cracking. For example, Changes in humidity affect the size, canvas, or wood

through swelling and contraction, causing cracks in the paint layers (Karpowicz 1990).

Although both panel and canvas are affected by humidity changes, only canvas is affected by

rolling, while panel by the wood grain. Artists affect the craquelure pattern with the materials

they choose, which is why there are regional similarities and why an artist's own paintings are

similar. Additionally, Canvas type, oils, glazes, all affect the crack pattern. Of course damage

caused by blunt force causes craquelure to form, but this is often noticeable for the spiral pattern

on the canvas.

Although there have been various attempts to map patterns based on the nature of the

proteins in size (Karpowicz 1990) or using a computer program (Bucklow 1999) those efforts

have not been hugely successful because of the complex nature of crack networks, both visually

and in the ways that they can form. Scientific analysis (as well as connoisseurship) is important

in establishing the veracity of a painting (Caple 2000, 80). In other words, it is difficult to map

these networks, but fairly easy to tell when a network is incorrect. In the case of craquelure, fake

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cracks are obvious to a trained eye when not done correctly. False cracks might be merely

painted on or not go all the way to the ground, like in Wigfield's case study (1998). Forgers have

developed more sophisticated techniques such as rolling. Aging with craquelure, size, sugar

paste have been attempted, but can be picked up through scientific examination or very good

connoisseurship (Craddock 2009).

Jean-Honoré Fragonard's French work, The Education of the Virgin, was painted with oil

on panel (Fig. 1). Fragonard painted in the 18th century in a Rococo style. He primarily worked

in France, but also traveled to Italy to study. The Education of the Virgin was painted early on in

his career. This painting exhibits horizontal primary cracks equidistant and parallel about 1/4"

apart. They curve slightly, following the grain of the wood panel. The secondary cracks are

small and resemble rectangular webbing and exists perpendicular to the wood grain. In

Bucklow's article, he identified French work as having a random craquelure network, but that

was because he was only examining works on canvas, not works on panel like this one (1999).

In Rembrandt's Dutch work, Juno, done with oil on canvas the pattern is completely

different(Fig. 2). Juno was painted towards the end of his career Here the primary cracks on

the lighter colored flesh area of Juno vary in island size and overall pattern. Yet, there is a

pattern of parallel, regular, secondary cracks running laterally, just as in Fragonard's work.

Fig. 1 Jean-Honoré Fragonard. The

Education of the Virgin. 1748-52.

Hammer Museum.

Fig. 2 Rembrandt Harmensz, Van Rijn.

Juno. ca. 1662-65. Hammer Museum

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There do not seem to be craquelure on the darker areas of his painting, but they might just be

very difficult see because of Rembrandt's darker color choice. Rembrandt is known for layering

darker colors, so the pigment and binders used may have been different and therefore may have

affected the craquelure pattern.

In Honoré Daumier's French work, The Lawyers, he chose to paint with oil on canvas

(Fig. 3). Daumier was a French caricature artist and these paintings were made late in his career.

Along with bubbling in upper right the craquelure appeared random and radiating with large

distances between large islands. The bubbling in the corner is an example of parallel disruption

according to Stout, which is of the shell clef variety (1977). Parallel disruption means that the

disruption is parallel to the canvas plane, rather than reaching down through to the ground as a

perpendicular, or craquelure, disruption would. The craquelure in this example has been

highlighted with red for visibility. The second Honoré Daumier painting was quite different,

The Holy Water Sprinkler, presumably because it was oil on panel instead of oil on canvas (Fig.

4). This painting exhibited a regular parallel pattern of cracking, much like Fragonard's work,

with rectangular islands. The parallel cracks presumably run with the grain of the wood, while

Fig. 3 Honoré Daumier. The Lawyers. 1860. Hammer Museum.

Fig. 4 Honoré Daumier. The Holy Water Sprinklet. n.d. Hammer Museum.

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branches of smaller cracks are found between, against the grain. A look at the wood panel would

be needed to verify this statement.

Gilbert Stuart, an American painter, painted this, a Portrait of George Frederick Nugent,

Seventh Earl of Westmeath, with oil on canvas (Fig. 5). He painted this portrait in the middle of

his career. Although he painted mostly in the United States, he did study in the United Kingdom

at the beginning of his career. Here we see yet another pattern; arc-line fork cracks (according to

Stout) that permeate the painting, with smaller cracks radiating from the corners. Waves

radiating from corners are caused by drying a layer of size at a low tension (Kapowickz).

This study demonstrates that materials used do have an effect on the craquelure networks

(Bucklow 1997). In general the paintings on canvas had more varied patterns, paintings on panel

were more likely to have evenly spaced craquelure consisting of branching lines. Although

material seemed to have more effect on the resulting crack pattern, locality also had an effect as

seen in the distinct difference between the French and American paintings. Additionally, studies

of craquelure patterns can offer insight into the techniques of each artist. In the Stuart example,

we saw that he dried his paintings at a low tension, which caused the wave craquelure network. It

is interesting, though not surprising, that the craquelure patterns were not consistent across one

painting. Especially in the paintings on canvas, a craquelure pattern might vary according to the

area of the paintings. This was probably because there were different tensions on that area when

Fig. 5 Gilbert Stuart. Portrait of Frederick Nugent, Seventh Earl of Westmeath. ca. 1790-92. Hammer Museum.

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drying and different areas were painted with different pigments and binders. In lecture, Dr. Scott

demonstrated how different areas settled to varying extent, causing variation in the craquelure

networks.

Although an amateur conservator's eye revealed quite a bit about the nature of craquelure,

scientific study through x- radiograph and other methods would reveal much more about these

patterns. Study of all aspects of a painting helps us identify forgeries and reveal important

information about a work that we would not have otherwise known, thus enriching the universal

knowledge of art and history.

BibliographyBucklow, Spike. "The Description and Classification of Craquelure." Studies in Conservation no. 44

(1999). pp. 233-244.Bucklow, Spike. "The Description of Craquelure Patterns." Studies in Conservation no. 42 (1997). pp.

129-140.Caple, Chris. Conservation Skills: Judgement, Method and Decision Making. Routledge, 2000.Craddock, Paul T. Scientific Investigation of Copies, Fakes and Forgeries. Routledge, 2009. Karpowicz, Adam. “A Study on Development of Cracks on Paintings.” Website, 1990.

http://cool.conservation-us.org/jaic/articles/jaic29-02-005_3.html. Accessed January 27, 2014.Stout, George L. “A Trial Index of Laminal Drisruption.” Journal of the American Institute of

Conservation, no. 17 (1977). pp. 17-26.Zilbergleyt, Boris. “Forecast of Chemical Aging and Related Color Changes in Paintings.” E-

Conservation Magazine no. 7 (n.d.). Wigfield, Elizabeth. "Examination of a painted craquelure on a 17th-century Dutch marine painting

attributed to Willem Van de Velde the Younger: A Case Study." The Conservator, no. 22 (1998). pp. 17-25.