Figure F43. Gabbro in which orthopyroxene (Opx) is replaced by colorless and pale green amphibole (Am) along fractures and cleavage surfaces. Olivine (Ol) is completely replaced by tremolite, talc, serpentine, and clay minerals. Coronitic chlorite (Chl) formed between olivine and plagioclase (Pl) is common but is lacking at the contact with orthopyroxene (Thin Section 29; Sample 345-U1415J-3R-1, 11–13 cm [Piece 4]). A. Plane-polarized light. B. Under crossed polars.
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