FIG. 5. BSE images showing the habit and association of Bi-tellurides in ‘geode’ type ores; all from sample: 71 (0 Est gallery). (a) Included blebs of tellurides (bright white) within pyrite (Py). Sp: sphalerite; Cal: calcite. (b) Composite inclusions of hessite (Hs) and altaite (Alt) within pyrite (Py). (c) Similar bleb-like telluride inclusions within pyrite (Py), consisting of hessite (Hs), altaite (Alt) and volynskite (Vl). (d) Composite, bleb-like inclusions in pyrite (Py), consisting of hessite (Hs), altaite (Alt) and a decomposition intergrowth with a bulk composition approximating to Ag₃Au(S,Te)₂. Note curvilinear equilibrium boundaries.