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-- T-4518 66 Chalcopyrite, tetrahedrite, tennandte, prousdte, pyrazgyrite, famatinite, and stroroeyerite comprise the sulfosalt stage of mineralization. Famadnite and some tennantite and tetrahedrite are assigned to this stage of mineralization despite ambiguous textural relationships indicating either codeposition with the base-metal stage or replacement during the sulfosalt stage. ' Pyrazgyrite, prousdte, chalcopyrite, and tennantite occur as 5 to 20 µm grains in. fractures (Figs. 41a and b). Although not distinguishable in Figure 41a, pyrazgyrite lines the fracture while proustte fills the center of the fracture, suggesting that the latter was deposited after the former. Galena and some chalcopyrite shown in Figure 41b may belong either to the base-metal stage, or gossibly to the sulfosalt stage. The former interpretation is more plausible because galena was not seen filling fractures elsewhere. Famatinite was found in only one sample as irregulaz 10 to 20 µm blebs in sphalerite (Fig. 42). The blebs could have been deposited with sphalerite, exsolved from it, or occur as later replacements of sphalerite or chalcopyrite. The latter interpretation is , favored for two reasons: 1) famatinite is an antimony sulfosalt like other, clearly late, e minerals in the sulfosalt stage; and 2) one bleb appears to be replacing a bleb of chalco te. Tetrahedrite u to 300 m) and tennanrite (u to 50 m a eaz tore lace PYt'i (P µ P µ ) PP P s- sphalerite as irregulaz, anhedral grains which could also be interpreted as codepositional I-- with it (Figs. 43a and 436). Stromeyerite fills wgs in sphalerite (Fig. 43c) and, as previously noted, replaces the second base-metal stage of chalcopyrite (Fig. 36). The presence of stromeyerite, prousdte, pyrazgyrite, tetrahedrite, tennantite, and famatinite were confirmed by semi-quantitative microprobe analyses. An effort was made