Application example: The story of a porcelain snuff box

Confirming or disproving the authenticity of artworks requires expert evaluation in terms of artistic style and fabrication technique. Regarding the latter, non-destructive materials science methods such as ion beam analytics can reveal helpful information about the object.

An 18th century Meißen porcelain snuff box raised doubts about its full authenticity due to deviating glaze colorations and differences in the brush stroke of the lid and bottom. A combination of the ion beam analytics methods of PIXE (proton-induced x-ray emission), PIGE (proton-induced gamma emission), and RBS (Rutherford backscattering) revealed the elemental compositions of the glazes and a characteristic green paint in both lid and bottom of the snuff box. This investigation showed that both differ markedly: The green paint of the bottom contained a significant amount of an iron-based pigment, which is missing in the green paint of the lid. The glaze of the bottom is high in lead content, which is in stark contrast to the composition of the lid glaze. The lid glaze was identified as typical Meißen glaze of the 18th century by comparing its composition with that of verified Meißen porcelain sculptures of the same period. Given these differences between the bottom and the lid, the snuff box was apparently not preserved in its entirety over time. Still, the bottom may originate from the Meißen manufacture, which used lead-based glaze until 1730. In a plausible scenario, the box was initially produced before 1730. After 1730, a broken lid was replaced by a new one from the Meißen restoration workshop. By then, the glazing technology had changed, and the new lid was decorated by a different painter.

The case of the Meißen porcelain snuff box highlights, how non-destructive ion beam analytics can help to check an objects authenticity and reconstruct its unique history.

• C. Neelmeijer and R. Roscher, PIXE-RBS survey of a Meissen porcelain snuff box: first version or not?
  X-ray Spectrometry 41 (2012) 93
  https://doi.org/10.1002/xrs.2371