Figure 8. Formation of irregular silica surface textures on Microfacies 1 sinter. (1) Clusters of coalesced silica spheres. (2) Close-up of (1) showing ill-defined outlines. (3) Anastomosing  ridges and cavities at various stages of formation. (4) Incipient occurrence of ridges, associated cavities, and nodules (red arrows). Note broad deposition of secondarily deposited silica spheres (yellow arrows). (5) Early-stage occurrence of nodules, acquiring a cone to round shaped surface. (6) Late-stage occurrences of nodules, exhibiting necking (red arrows).