FIG. 10. Means of Pb and Ag composition (wt.%) for various short- and long-period polysomes stable within the range padraite-cuprobismutite (discussed in the text and Table 3), as identified from the lattice images in Figs 3b, 4b and 8. They represent similar intermediate values to those obtained for the ‘Mix’ intervals of 5–10 µm width in the CBP (Figs 2e,f and 4a; Table 2). The Pb values representing the polysomes cluster around 4 wt.% Pb, irrespective of the number of ribbons they encompass.