Skip to main content
. 2019 Jan 9;5(1):eaau7126. doi: 10.1126/sciadv.aau7126

Fig. 3. Elemental composition of archaeological blue particle and blue reference pigments measured by EDS.

Fig. 3

(A) Blue particle isolated from medieval dental calculus. (B) Afghan lazurite reference pigment (RC, 410-15). (C) Azurite reference pigment (RC, 410-10). (D) Smalt reference pigment (RC, 417-14). (E) Vivianite reference pigment (RC, 410-20). The archaeological blue particles lack copper (Cu), cobalt (Co), and iron (Fe) but closely match the spectrum produced by the tectosilicate lazurite. Scale bars, 20 μm. Additional reference spectra are provided in fig. S7. Raw data are provided in data file S2. Credit: M. Tromp.