FIG. 2. BSE images showing cuprobismutite homologues and padraite. (a) Needles (5-10 µm) of cuprobismutite (Cbs) with pyramidal termination. The matrix consists of over-substituted bismuthinite (BD₁₀) with fields of fine intergrowths. The average composition within such fields is in the range between gladite and pekoite (BD_32-16). (b) Area with mixed composition between padraite (Pad) and Cbs. Several narrow bands with Cbs composition are seen in the middle part. (c) Orthogonal aggregates of cuprobismutite-padraite (CBP) in a matix of BD₁₀. Note the stepwise arrangement of laths, with lath-width reducing towards the interior of the aggregate. Makovickyite (Mak) and gladite (Gl) are seen as darker shades than the matrix between the laths. (d) Hodrushite (Hod) and Cbs in a lath dominated by Pad. (e and f) Details of laths within cuprobismutite-padraite aggregates (CBP) showing Pb (wt. %) variance across sequences of alternating cuprobismutite (noted as ‘C’), padraite (‘P’) and mixed material in the Cbs-Pad range (‘M’). In (e), the lower marginal needle of Cbs crosscuts the boundary of makovickyite (Mak) towards BD₁₀. The points mark the line of the profile. (g and h) Diagrams showing the bimodal variance of Pb (in wt.%) across the sequences in (e) and (f), plotted as difference between two adjacent intervals of 5–10 µm each.