Art Expertise / Expert Consultancy
“Before you invest, investigate”. J. Paul Getty, 1892-1976
The attribution and dating of decorative and fine arts are extremely problematic areas, and mistakes can be costly. With over 30 years as a conservator (and an original training as a maker, with an inside view of Parisian workshops), Yannick Chastang is in an unparalleled position to advise potential buyers about the condition and the probable origin or date of a piece of furniture or bronze. He can be consulted before large sums of money are invested, to study an object or in case of a dispute.
Yannick Chastang advises private collectors, national museums and auction houses about buying, authenticity and conserving heritage houses and their collections. He vetted the furniture at The European Fine Art Fair (TEFAF) at Maastricht for 18 years from 2004 to 2022, including two years as the head of furniture vetting group. In 2015, he wrote the new TEFAF vetting guidelines for the furniture group. He resigned from TEFAF in 2023 because these guidelines were not being followed and vetting decisions were being overruled or ignored. Yannick vetted at Masterpiece in London for 5 years before resigning for similar reasons.
Yannick has been an external adviser to the Louvre Museum in Paris, the National Trust in England, the Bayerische Museum in Munich, and the Parliament House in Helsinki, Finland. Yannick regularly teaches and lectures in the UK and abroad.
Yannick has written a book about French marquetry and numerous articles about the conservation and history of decorative arts. He is a contributing author of two volumes from A Cultural History of Furniture, 6 volumes, and a contributing author of the Getty Catalogue of Rococo Furniture.
Over the years, Yannick has been an expert witness on legal cases (Partridge in London and French furniture fake scandals). He currently helps major collectors and major auction houses around the world with technical studies and scientific analysis of objects offered for sale or after acquisition. Yannick is independent of the antique trade, he does not charge commission based on the value of the item, his charges are fee-based.
The study and analysis of the materials used during the making of decorative and fine arts helps greatly with the dating of object, as many materials of the past centuries are not available anymore or are extremely difficult for fakers to replicate. For example, compositional analysis of bronze and copper alloys involves the determination of the identities and concentrations of the constituent elements of the metal or alloy. The levels of impurities in metals are good indicators of the manufacture process used. The dating of historical copper alloys, iron, steel and their impurities is based on the understanding of historical technical developments and the scientific analysis of hundreds of dated objects from major museums and private institutions around the world. Yannick has developed the largest scientific database and photographic database in private hands, with thousands of reference analyses to help with the dating of decorative arts, using some of latest X-ray fluorescence techniques and the best microscopic analytical tools.
Using some of the latest analytical equipment, database analytical tools and Machine Learning software, the dating of copper alloys (gilt bronzes and sculptures) is becoming increasingly precise and extremely reliable. It is now possible to distinguish original 18th century pieces from later copies, often with a precision of dating of + or – 20 years. Please call for more details of what Yannick Chastang can offer.
Trianon commode attributed to A. C. Boulle, c.1715. Petworth House, National Trust. Technical study and analyisis
Boulle commode attributed to Joseph Poitou, c.1715. Technical study and Xrf dating
Boulle table attributed to A. C. Boulle. Sotheby's New York. Xrf analysis and technical study
Bronze Hercules. 16th century. Xrf analysis and dating
Gilt Bronze Chandelier attributed to A.C. Boulle. Analysis and dating by Xrf and iron metallurgical analysis
Cabinet on stand attributed to A. C. Boulle, c.1680. Christie's Paris. Technical study.
UV light examination of Asian and European lacquer
Cabinet on stand attributed to Pierre Gole made for the Duchesse de Fontanges, c.1680. Xrf analyisis and Technical study. Musée Jacquemart-Andre
Cabinet on stand attributed to Pierre Gole, c.1680. Nostell Priory, the National Trust. Technical study
Commode previoulsy sold as attributed to A.C. Boulle. Re-dated c.1980 after technical study and Xrf analysis of brass marquetry and gilt bronzes jpg
Analysis results of a typical 20th century fake bronze in the style of Giambologna. The bronze alloy composition is modern and contains no impurities.
Eléphant au repos by Rembrandt Bugatti, c.1912. Xrf analysis confirmed dating
Yannick Chastang. Microscopic study of pigment
Pigmented glue analysis, Boulle coffer, c.1700
Boulle desk attributed to A. C. Boulle. Sotheby's New York. Xrf analysis and dating
Farnese Hercules attributed to Susini, 17th cnetury. Xrf analysis confirmed dating and attribution
Gilt Bronze and porcelain clock. 18th century porcelain with later bronzes. Xrf analysis
Yannick Chastang TEFAF resignation 2023
Equestrian statue of Louis XIV by Antoine Coysevox, early 18th century. Xrf analysis and dating prior to the acquisition of the statue by the Musée des beaux-arts de Rennes
Gilt bronze clock previoulsy sold and published as being late 18th century. Analysed by Xrf and re-dated c.1850
L'homme de Villetaneuse, by César. 1954. Xrf Analysis. Private Collection, France
Mounted vase attributed to Jean-Claude Duplessis, c.1755. Analysis and dating confirmed by Xrf
Non destructive Xrf analysis of gilt bronzes attributed to A.C. Boulle, c.1700
Technical study of c.1700 locks at Boughton House, the Duke of Buccleuch and Queensberry
Yannick Chastang lecturing at the J.Paul Getty Museum, Los Angeles
Yannick Chastang lecturing in Philadelphia, USA in 2022
Yannick Chastang. Xrf analysis of Boulle furniture at the J.Paul Getty Museum, Los Angeles
Yannick Chastang's first visit to the J.Paul Getty in 1995, aged 21