Figure F126. Photomicrograph showing pyrite in an irregular 10-µm-wide veinlet, filling pores and a vesicle, replacing silicate minerals, and along grain boundaries within slightly altered dark gray basalt (Sample 206-1256D-38R-1, 10-12 cm; field of view = 2.5 mm; reflected light).

Figure F126. Photomicrograph showing pyrite in an irregular 10-µm-wide veinlet, filling pores and a vesicle, replacing silicate minerals, and along grain boundaries within slightly altered dark gray basalt (Sample 206-1256D-38R-1, 10-12 cm; field of view = 2.5 mm; reflected light).