Figure 4. (a) The packet-size distribution and (b) aspect ratio of bioreduced smectite (BS) and non-reduced control (NC) showing an increase in mean packet size (11.4 nm to 23.9 nm) and aspect ratio (0.11 to 0.18). The errors of the measurements are typically ±5%. The measurements were made on TEM lattice-fringe images using a microfiche reader.