Joint 44th AIC Annual Meeting & 42nd CAC-ACCR Annual Conference – “Carlo Crivelli's St. George Slaying the Dragon at the Isabella Stewart Gardner Museum: Technique and Restoration.” Speaker: Gianfranco Pocobene, May 17

An Altarpiece Reunited.  Isabella Stewart Gardner Museum.  2015.  Web.  30 May 2016 <>.
Carlo Crivelli’s St. George Slaying the Dragon was completed in 1470 as one of six panels in the Porto San Giorgio Altarpiece.  After the church was demolished in 1803, this altarpiece was disassembled and individual panels dispersed to collections throughout Europe and the United States.  The Isabella Stewart Gardner Museum (ISGM) acquired St. George Slaying the Dragon panel in 1897.
Since arriving at the museum, Carlo Crivelli’s painting has undergone two conservation treatments: one by George Stout during 1934-1935 and the other by Pocobene and his team during 2013-2015.  The 2013-2015 treatment was conducted in anticipation of the ISGM’s exhibition Ornament and Illusion: Carlo Crivelli of Venice (10/22/2015–1/26/2016).  This was the first exhibition featuring Crivelli to be held in the United States and the St. George panel was selected to be one of the centerpieces.
St. George was constructed using traditional Venetian techniques and materials including egg tempera paint, ornamental relief, and gold leaf gilding.  These layers were visible along some of the periphery edges.  Worm tunnels in the upper right edge indicate the poplar panel had previously been trimmed-down, likely during the time the six altarpiece panels were separated.  Low relief forms, known as pastiglia, were built-up in the armor, halo, forehead gemstone, and the horses bridal and reigns.
In preparation for the Ornament and Illusion exhibition, an extensive examination was performed including X-radiography, IR, RTI, XRF, and SEM analyses.  The resulting X-radiograph revealed lead white in the original paint layers as well as dense lead putty fills during the previous restoration.  Infrared reflectography revealed both carbon black ink underdrawing and contour line reinforcements in bone black paint (the presence of this paint made it difficult to discern the underdrawing).  Reflectance transformation imaging revealed the fish scale textures in the armor and sword hilt.  X-ray fluorescence revealed lead white, earth pigments, vermillion, red lake, and azurite in the blue-scale fish pattern, and silver in the armor (indicating that the brown-black color is actually tarnished silver leaf).  Scanning electron microscopy analysis was performed by Richard Newman at the MFA Boston.  After cross sections from the armor were analyzed with SEM, the presence of silver leaf was confirmed, conversion of the silver leaf to a silver sulfide, and a surface layer of bone black covering the leaf.  In addition to the technical analyses, images from 1926 and documentation from the 1934-1935 restoration were also referenced.
NormalLight_vs_IRR  NormalLight_vs_RTI
During the 2013-2015 treatment, the cleaning process focused on removing grime, the old PVA varnish, yellowed wax coating, and old restorations that no longer matched the original paint layers.  Fills, inpainting, and regilding was employed to restore the panel painting.  In order to maintain its aged appearance, the 23k gold leaf and shell gold applied in a few selected areas of the sky and abraded pastiglia to reintroduce more vibrancy and hint at the original finish.  If you would like to learn more about this treatment or about the Ornament and Illusion exhibition, please visit:
About the authors:
Gianfranco Pocobene earned his M.A. in Conservation from Queen’s University and holds a Certificate of Advanced Training in Paintings Conservation from the Harvard Art Museums. For the past thirty years, Pocobene has worked as a paintings conservator in the United States and Canada, and for the past twelve years, he has been the John L. and Susan K. Gardner Chief Conservator at the ISGM.
Jessica Chloros earned her M.S. in Art Conservation from the Winterthur/University of Delaware Program in Art Conservation.  For the past eight years, Chloros has worked as an associate objects conservator at the ISGM.
Richard Newman earned his B.A. in art history from Western Washington University, M.A. in geology from Boston University, and Certificate from the Center for Conservation and Technical Studies, Fogg Art Museum, Harvard University.  For the past thirty years, he has worked as a conservation scientist at the Museum of Fine Arts, Boston.  Newman is currently the Head of Scientific Research at the MFA, Boston.