Figure F5. Photomicrograph, with crossed polars, of Sample 187-1158B-2R-1 (Piece 1, 0-4 cm; see "Site 1158 Thin Sections"), showing a plagioclase microphenocryst with concentric oscillatory zoning (top right) in a groundmass of plagioclase and clinopyroxene. The circular feature in the phenocryst is a glue bubble.