AC LOSER LOOK Technical and Art-Historical Studies on Works by Van Gogh and Gauguin CAHIER VINCENT 3 A CLOSER LOOK CAHIER VINCENT 3 Rijksmuseum Vincent van Gogh in cooperation with the Vincent van Gogh Foundation A CLOSER LOOK Technical and Art-Historical Studies on Works by Van Gogh and Gauguin Edited by Cornelia Peres, Michael Hoyle and Louis van Tilborgh With contributions by Mette Marie Bang, Paolo Cadorin, Judith Hofenk de Graaff, VojtechJirat-Wasiutynski, Cornelia Peres, Carol Stringari, H. Travers Newton Waanders Publishers, Zwolle Contents 7 Foreword 8 Note for the Reader I2 Colour Fading in Van Gogh and Gauguin Paolo Cadorin II VAN GOGH'S TRIPTYCH OF ORCHARDS IN BLOSSOM 2 I Introduction 24 An Impressionist Concept of Painting Technique Cornelia Peres 39 On Egg-White Coatings Cornelia Peres 57 Van Gogh's Palette Mette Marie Bang 6I Examination and Treatment Carol Stringari 75 Scientific Investigation Judith H. Hofenk de Graaff et al. III GAUGUINS PORTRAIT OF VINCENT VAN GOGH PAINTING SUNFLOWERS 8 7 Introduction 90 Paintingfrom Nature versus Paintingfrom Memory Vojtech Jirat-Wasiutynski I03 Observations on Gauguin's Painting Techniques and Materials H. Travers Newton I I 2 Condition and Conservation Report Cornelia Peres Foreword This CAHIER VINCENT examines two recent restoration projects involving works in the collection of the Van Gogh Museum (Vincent van Gogh Foundation): Gauguin's Portrait of Vincent van Gogh Painting Sunflowers, which has not been on display for several years because of the deterioration of its jute support, and Van Gogh's Aries triptych of orchards, consisting of The Pink Orchard, Peach Trees in Blossom and The White Orchard. These restorations, which were carried out on the eve of the 1990 Van Gogh centenary, brought a great deal of new information to light and gave us a deeper understanding of the artist's working method. The purpose of the CAHIERS VINCENT series is to make source material available to the international community ofVan Gogh scholars. This latest volume, which presents the results of restoration projects, departs from that aim to the extent that this time it is not documents that are the primary source, but some of the artist's own paintings, which have yielded a valuable insight into the way they were exe cuted. There is a growing realisation that the pictures in our care have undergone a considerable transformation since they were painted over a century ago. Leaving aside deliberate interventions during earlier conservation treatments, it has been time itself that has wrought the greatest changes. Many pigments, for example, have lost much of their original hue, which has occasionally brought about dramatic shifts in the balance between different passages within a painting. We have to be fully aware of these discolourations if we are to interpret the pres ent image correctly. With an artist like Van Gogh, who was intensely interested in colour theory, it is essential to supplement the evidence of one's own eyes with the knowledge obtained from specialists. The Van Gogh Museum's conservator, Cornelia Peres, was responsible for the general concept of this CAHIER, and for inviting the international group of contributors, comprising conservation specialists, scientists and art historians. Among these I would like to single out Paolo Cadorin, not least because Ms. Peres received her first training under his guidance. On behalf of the joint editors, Cornelia Peres and Louis van Tilborgh, I would like to express our debts of gratitude to all those who have been directly or indirectly involved in the conservation treatment of the works under discussion, and in particular to guest conservators Carol Stringari and H. Travers Newton, conservation assistant Mette Marie Bang, art historian Vojtech Jirat-Wasiutynski and, last but not least, to our colleagues at the Centraal Laboratorium in Amster dam. During the editorial stages this CAHIER benefited immensely from the expert advice of conservator IJsbrand Hummelen and translator Michael Hoyle. Rene Gerritsen carried out most of the technical photography in the Van Goghmuseum. As with the previous volumes in this series, we are grateful to the Vincent van Gogh Foundation for its financial support. Ronald de Leeuw Director Rijksmuseum Vincent van Gogh CAHIER VINCENT 3 7 Note for the Reader Most of the articles were written before March 1990, so CL subsequent literature on nineteenth-century painting tech Central Research Labatory for Objects of Art and Science. niques, most notably the exhibition catalogue Art in the * Making. Impressionism, London (National Gallery) 1990-91, The following difmitions of analytical techniques are given is not cited. Nor has use been made of the renumbering of relative to their use for the investigation of artists materials. This Van Gogh's letters in the recent Dutch edition, De brieven analytical instrumentation has been employed for many years in van Vincent van Gogh, ed. Han van Crimpen and Monique the scientific community for different purposes and is presented Berends-Albert, The Hague 1990. here only in the service of conservation science. The following abbreviations are used throughout this CAHIER. EDX Energy dispersive x-ray analysis is useful for the detection of The F numbers refer to the relevant catalogue numbers in elements present in a pigment sample or cross-section of the J.-B. de la Faille, The Works of Vincent van Gogh, Paintings paint layer. For cross-section analysis, it is particularly appli and Drawings, Amsterdam 1970. cable for layer by layer characterization. The outcome of the elemental analysis in conjunction with optical micro The w numbers refer to the relevant catalogue numbers in scopy can lead to the determination of the actual pigments. G. Wildenstein and R. Cogniat, Paul Gauguin, vol. r, Paris The technique employs an electron beam from an SEM 1964. (scanning electron microscope) which generates x-rays at a specific point of the specimen. The resultant x-ray emission Number of cited letter [ ] in The Complete Letters of Vincent spectrograph displays the characteristic energies of the ele van Gogh, 3 vols., London 1958 ments present. The information gained is both qualitative and quantitative. GAC Letter in Douglas Cooper (ed.), Paul Gauguin: 45 Lettres d FTIR Vincent, Theo et ]o Van Gogh, Collection Rijksmuseum Fourier traniform infrared-spectrometry is an especially effective Vincent van Gogh, Amsterdam, The Hague & Lausanne analytical technique for the determination of organic and 1983. inorganic materials such as pigments, binding media and synthetic resins. The method is chosen for the high sensiti Jirat-Wasiutynski et al. vity and resolution. FTIR involves the coupling of an optical VojtechJirat-Wasiutynski, H. Travers Newton, Eugene system of analysis with a computer which transforms the in Farrell and Richard Newman, Vincent van Gogh's formation gained to produce a high quality spectrum on a 'Self-Portrait Dedicated to Paul Gauguin': an Historical and graphic chart. The peaks are specific to the chemical func Technical Study, Cambridge (Mass.) 1984. tional groups present. The infrared region spectral chart is 8 CAHIER VINCENT l