Article: differentiation of layers by optical microscopy (2008)

Title: The visible image is not always correct: the differentiation of layers by optical microscopy in samples’ cross sections
Author: Carolina Barata, António João Cruz, Marta Ferro
Reference: e-conservation, 7, 2008, pp. 21-25
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Abstract:

The stratigraphic characterization of polychrome surfaces in works of art is frequently done through the observation of cross-section samples by optical microscopy (OM). Three examples that show some limits to this method are presented here. In samples where at first only one layer was visible, several strata were detected through electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS). These and other examples ought to be taken into consideration by conservators, who should be aware of similar possibilities in other cases.