Figure F69. Alteration front between a black halo (two euhedral olivine phenocrysts replaced by nontronite, lower right) and the gray basalt interior (two euhedral olivine phenocrysts replaced by saponite, upper left) in Sample 192-1183A-67R-1 (Piece 2C, 46-48 cm) (field of view = 5.5 mm; plane-polarized light; photomicrograph ID# 1183A

Figure F69. Alteration front between a black halo (two euhedral olivine phenocrysts replaced by nontronite, lower right) and the gray basalt interior (two euhedral olivine phenocrysts replaced by saponite, upper left) in Sample 192-1183A-67R-1 (Piece 2C, 46-48 cm) (field of view = 5.5 mm; plane-polarized light; photomicrograph ID# 1183A_030).