Fig. 3
From: Genetic optimisation of bacteria-induced calcite precipitation in Bacillus subtilis
Scanning electron microscopy of calcite crystals produced by strain W∆-H-BpU. Mineral crystals formed after incubation of strain W∆-H-BpU on LBC-phenol red agar for 2 weeks at 30 °C and 1 week at room temperature were removed from the colony surface and imaged by scanning electron microscopy with gold splutter coating. A–D Sequential zoom in on a crystal particle. The white boxes in panels A and B indicate areas of view shown in the subsequent panels. White arrows indicate the different sized stages of crystals in the commonly observed ‘dumbbell’ morphology. Open arrows indicate the web-like material observed between the dumbbell shaped crystals. E EDX elemental analysis was performed at two image sites (S1 and S2) indicated in panel C to verify the precipitate composition was predominated by calcium (Ca), carbon (C) and oxygen (O)