Laboratory Portrait: Analysis of Art Works and Nuclear Physics at the Laboratory ofCentre de recherche et de restauration des musées de France

Lead-GlazedRustiques Figulines(Rustic Ceramics) of Bernard Palissy (1510-90) and his Followers

“…The results for the 19th century objects are very different (Table ); two test palettes of Avisseau have been studied (Castaing and Menu ); the one shown in Figure S4 contains up to 16% B 2 O 3 in the blue glaze, and 13% B 2 O 3 in the brown glaze, in agreement with the widespread use of boron at that time (Speel and Bronk ). If present in the 19th century artefact produced by Pull (Fig.…”

“…Castaing and Menu () analysed for the presence of B 2 O 3 in ceramic glazes on objects of various ages using PIGE; boron was found only in objects fabricated after the Renaissance. No objects known to be from the 16th century (or earlier) contained boron at concentrations detectable by PIGE.…”

“…The B 2 O 3 concentrations are determined by comparison with PIGE boron peaks of a standard glass (e.g., NIST 93a, containing 12.6% B 2 O 3 ). The detection limit in our accelerators is between 0.1% and 0.3% B 2 O 3 , depending on the ion‐beam intensity and the sensitivity of the γ‐ray detection system (Castaing and Menu ).…”

“…One interesting finding from analyses of genuine Palissy objects and those of later provenance is that the presence of B 2 O 3 , even in quantities as small as 0.1%, precludes a 16th century origin for any object, as Palissy and other artists of that time apparently never used boron in any of their glazes (Castaing and Menu ). However, the absence of B 2 O 3 in any glaze on a Palissy‐style object does not confirm a 16th century origin.…”

“…In both laboratories, the GUPIX code was used for PIXE data reduction to obtain elemental concentrations. For boron, concentrations are determined from the ratio of peak areas in the PIGE spectra for objects under study compared to standards (Castaing and Menu ). Identical standards were used for calibration in the two laboratories.…”