Figure 33. A. Photograph of semimassive sulfide consisting of pyrite and chalcopyrite grains in an anhydrite-silica matrix. Angular white fragments are altered volcanic rock (interval 193-1189A 12R-1, 120–128 cm). B. Photomicrograph of volcanic clasts with fibrous, laminate internal texture, which are abundant in this sulfide-rich interval (Sample 193-1189A-12R-1 [Piece 16, 122–125 cm]; field of view - 1.4 mm).