Figure F80. A 3- to 4-mm-wide vein of calcite (near walls) with chalcedony and quartz (center) in Sample 192-1183A-66R-2 (Piece 4B, 60-64 cm) (field of view = 5.5 mm; plane-polarized light; photomicrograph ID# 1183A

Figure F80. A 3- to 4-mm-wide vein of calcite (near walls) with chalcedony and quartz (center) in Sample 192-1183A-66R-2 (Piece 4B, 60-64 cm) (field of view = 5.5 mm; plane-polarized light; photomicrograph ID# 1183A_032).