Pigments in sixteenth-century European painting

Marika Spring, Scientific Department, National Gallery, London

Abstracts from Academic Workshops (2007-8)
Funded by the Arts and Humanities Research Council

Over the last few years, as part of the programme for revision of the scholarly catalogues, full technical examinations have been carried out on many of the sixteenth-century German, Netherlandish and Italian School paintings in the National Gallery. The results of analysis give a good overview of the pigments in sixteenth-century European paintings, which could provide a context in which to place the results from the Tudor paintings project. Many pigments were available all over Europe. However, it is interesting to consider whether there are distinct geographical characteristics in the way in which they were used, or whether local materials not available everywhere can be identified.

The pattern of use of blue pigments confirmed what had already been established; for example the more frequent use of high quality ultramarine in Italian paintings. It was also used extensively in Netherlandish paintings, but only three occurrences were found among the paintings in the German school catalogue. This may be for reasons of cost or availability, but it might also be because German painters had access to extremely good quality azurite. That in Saint Peter's robe in Saints Peter and Dorothy by the Master of the Saint Bartholomew Altarpiece (NG 707, 1505-10) is of an intense colour that rivals ultramarine.

The purple mineral fluorite (calcium fluoride) has occasionally been used as a pigment. Most of the published occurrences are in South German or Austrian paintings, from close to major sources of the mineral in the Tyrol and the Black Forest. One of the new discoveries during the cataloguing programme was that it was also used in Netherlandish paintings; so far, it has been found in six of those in the National Gallery collection. In the first of these workshops, Libby Sheldon reported the presence of fluorite in the purple sleeve of Baron Berners by Ambrosius Benson (NPG4953) in the National Portrait Gallery. This is thought to date from the middle of the 1520s, the same period as the National Gallery paintings containing fluorite. Netherlandish artists may have obtained the mineral from a local source in the Ardennes. There is also a famous deposit of purple fluorite in England, in Castleton in Derbyshire.

Another new discovery was the extensive use of colourless powdered glass. There are references to the addition of colourless powdered glass to paint in a number of documentary sources, including Richard Haydocke's 1593 translation of Lomazzo, which expands on what Lomazzo says by specifically mentioning that it was used as a drier. Several seventeenth-century documentary sources, many of them English, also suggest it should be added as a drier (see Spring 2004 for references). The presence of glass was first confirmed in paintings by Raphael, mainly mixed with red lake. In every example that has been analysed the glass contains manganese, which is known to be capable of acting as a siccative for oil; indeed it would be very suitable as a drier for the glazy transparent red paint. Further evidence that its purpose was to act a drier is the context in which it was used. It was found in the mordant gilding on the throne in Raphael's Ansidei Madonna (NG1171), where it cannot have been included for aesthetic reasons as it is hidden beneath gold leaf.

The composition of vessel glass has been extensively studied by archaeologists, and clear geographical distributions, related to the local materials that were used to make the glass, have been established. The composition of the glass in paintings follows the same geographical trends: the Italian paintings have all, so far, been found to contain glass of the soda-lime type, while no soda-lime glass has been found in the Northern European paintings. Instead, high lime or mixed alkali glass was used. It is clear that this is a material which could help to establish the geographical location in which a work was produced, in the same way that a gypsum ground usually indicates a painting from southern Europe while a chalk ground is usually found on northern European paintings. As it is widespread in European paintings of this period, it seems likely that it was also used by artists in England in the sixteenth century.

Bibliography

L. Campbell, S. Foister and A. Roy eds, compiled and written by R. Billinge, L. Campbell, J. Dunkerton, S. Foister, J. Kirby, J. Pilc, A. Roy, M. Spring and R. White, Early Northern European Painting, National Gallery Technical Bulletin, Vol.18, 1997.

M. Spring, 'Occurrences of the Purple Pigment Fluorite on paintings in the National Gallery', National Gallery Technical Bulletin, Vol. 21, 2000, pp. 20­27.

M. Spring, 'Pigments in sixteenth-century painting of the German School', in The pictorial technique of Grünewald and his peers, ed. P. Béguerie-De Paepe and M. Menu, Musée d'Unterlinden, Colmar and C2RMF-CNRS, 2007, pp. 136­144.

M. Spring, 'Raphael's materials: Some new discoveries and their context within early sixteenth-century painting', in Raphael's Painting Technique: Working Practices before Rome, Proceedings of the Eu-ARTECH workshop, London November 11th 2004, ed. A. Roy and M. Spring, Quaderni di Kermes, 2007, pp. 77­86.

M. Spring, 'Perugino's painting materials: analysis and context within sixteenth century easel painting', Postprints of the workshop on the painting technique of Pietro Vannucci, called il Perugino, organised by INSTM and LabS­TECH, Perugia April 14th­15th 2003, Quaderni di Kermes, 2004, pp. 17­24.