Pigment ID

Zinc oxide pigments (ZnO) were introduced in 1880. Titanium dioxide (TiO2) was introduced in 1920. If you find either in your painting, then it is either a) time limited or b) restored after those dates.
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This is the kind of information we can learn from x-ray fluorescence (XRF). Different pigments were used based on time and region - the more we learn about the composition of the painting, the more we learn about when and where it was created. In some cases, artists like Claude Monet used a specific set of pigments, which can help verify the original artist.

XRF is a technique which allows us to see the elements within a pigment. If you have a cadmium-baed pigment, we will see it. If you have lead white, we will see it as well. In essence, any element between Na and U can be identified (and yes, both can be used as pigments too). Employees of PRI have worked with hundreds of museums around the world, from the Metropolitan to the National Museum of Kyoto, in the XRF analysis of pigments.

A related technique, Fourir-Transform Infrared Spectroscopy (FTIR) can be used to identify the opposite end of the pigment spectrum. Here, we can identify organic molecules using the interaction of inferred photons with the outer electron shell.

Both XRF and FTIR are qualitative techniques - the heterogeneity and layering of pigments doesn't lend itself to quantitative analysis. But with positive IDs for the pigments used, we can contextualize your results. You can send your artwork to us for identification, or send us to your artwork. Either way, you can
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