Fig. 4
From: Analysing the glaze of a medieval ceramic fragment from the Durres Amphitheater in Albania
Classification diagrams for glasses from the surface and the body of the glaze. a Bivariate diagram As2O3/CoO vs P2O5 (in wt.%) for the glasses in the blue-sky decoration and the green-ocean matrix. b SiO2-PbO-Al2O3 + CaO + Na2O + K2O + As2O3 (in wt.%) classification diagram for the glass in the blue-sky decoration and the green-ocean matrix (modified following [13]). Grading ranges from 70 wt.% SiO2 to 50 wt.% SiO2. c SiO2-PbO-Al2O3 + CaO + Na2O + K2O + As2O3 (in wt.%) diagram for glass in the glazed body (modified following [13]). Grading ranges from 70 wt.% SiO2 to 50wt.% SiO2. d Bivariate diagram Al2O3 + CaO + Na2O + K2O (in wt.%) versus PbO/SiO2 ratio shows the glasses' crystallisation trend correlated with the different mineralogical phases. All type glasses (avg) refer to the average composition of all the glasses (Lct-Kfs-type glasses; Trd glasses; General glasses). Glass composition analyses are in Additional file 1: Table S2