Fig. 3From: Unusual pigments found in a painting by Giotto (c. 1266-1337) reveal diversity of materials used by medieval artistsOne typical particle of lead tin yellow type II. a Back scatter image showing it is composed of crystallites of PbSixSn1-xO3 (bright) aggregated within a glassy Si–Pb-Ca phase (mid-grey). b Spectra associated with various phases in the particle. The color of the line relates to the site indicated by that color in a Back to article page