Figure F48. Interstitial chalcedony is present among calcite spherules that fill a miarolitic cavity in a deeply altered, highly vesicular brown halo in Sample 192-1186A-37R-1 (Piece 4, 96-98 cm) (field of view = 0.7 mm; crossed polars; photomicrograph ID# 1186A

Figure F48. Interstitial chalcedony is present among calcite spherules that fill a miarolitic cavity in a deeply altered, highly vesicular brown halo in Sample 192-1186A-37R-1 (Piece 4, 96-98 cm) (field of view = 0.7 mm; crossed polars; photomicrograph ID# 1186A_235).