Figure F59. Miarolitic cavities, with alteration halos, are filled by the following succession of secondary minerals in Sample 192-1185B-20R-1 (Piece 4, 27-29 cm) (from walls to center): calcite, yellow smectite grading through orange iddingsite into goethite, and celadonite (top center). Plagioclase is unaltered, and the host rock contains no olivine or secondary-mineral pseudomorphs after olivine (overall alteration = 20%; field of view = 5.5 mm; plane-polarized light; photomicrograph ID# 1185B_215).