Figure F7. Enlarged view of a contact between jasperoid and wallrock in Sample 193-1189A-7R-1 (Piece 17, 99–102 cm; CSIRO 142697). The selvage of inclusion-free quartz appears to have grown continuously with the clear outgrowths of quartz grains within the jasperoid portion (left), whereas its jagged boundary against wallrock suggests replacement of the latter. A thin quartz veinlet in wallrock extends vertically from the selvage at an irregularity in the boundary. Within the jasperoid, there is a banding in the proportion of hematite; this is uncommon. Width of view = 0.64 mm. A. Ordinary light. B. Crossed polarizers.

Figure F7. Enlarged view of a contact between jasperoid and wallrock in Sample 193-1189A-7R-1 (Piece 17, 99–102 cm; CSIRO 142697). The selvage of inclusion-free quartz appears to have grown continuously with the clear outgrowths of quartz grains within the jasperoid portion (left), whereas its jagged boundary against wallrock suggests replacement of the latter. A thin quartz veinlet in wallrock extends vertically from the selvage at an irregularity in the boundary. Within the jasperoid, there is a banding in the proportion of hematite; this is uncommon. Width of view = 0.64 mm. A. Ordinary light. B. Crossed polarizers.