Fig. 4

Characterization of the enamels. Each of the first five rows corresponds to one enamel color: red (a–c), blue (d–f), white (g–i), yellow (j–l), and green (m–o); Left column microscopic images of the polished cross-sections; Center column BSE images; Right column Raman spectra of the characteristic colorant inclusions together with the corresponding reference (gray). Details of the BSE images (p, q): p of the yellow enamel glass matrix showing lead- and tin-rich white inclusions (1) and elongated dark gray inclusions (2); q of the green enamel glass matrix showing white inclusions consisting of lead and tin (1), light gray tin-rich inclusions (2), and bright white gold-rich inclusions (3)