Figure F107. A. Anhydrite-pyrite vein with a zoned alteration halo of very fine grained quartz grading outward into a zone of brownish clay minerals (Sample 193-1188F-31Z-1 [Piece 1, 1-3 cm] in plane-polarized transmitted light; width of view = 5.5 mm. Photomicrograph ID# 1188F_84; thin section 92). B. Anhydrite-pyrite vein crosscutting alternating quartz- and clay-dominated bands, which formed around another anhydrite-pyrite vein (Sample 193-1188F-14Z-1 [Piece 6, 102-105 cm] in plane-polarized transmitted light; width of view = 5.5 mm. Photomicrograph ID# 1188F

Figure F107. A. Anhydrite-pyrite vein with a zoned alteration halo of very fine grained quartz grading outward into a zone of brownish clay minerals (Sample 193-1188F-31Z-1 [Piece 1, 1-3 cm] in plane-polarized transmitted light; width of view = 5.5 mm. Photomicrograph ID# 1188F_84; thin section 92). B. Anhydrite-pyrite vein crosscutting alternating quartz- and clay-dominated bands, which formed around another anhydrite-pyrite vein (Sample 193-1188F-14Z-1 [Piece 6, 102-105 cm] in plane-polarized transmitted light; width of view = 5.5 mm. Photomicrograph ID# 1188F_67; thin section 80).