Figure 5. Direct measurement of smectite packet thickness and length on the TEM lattice-fringe images of (a) non-reduced control (NC) and (b) bioreduced smectite (BS). The boundaries of packetswere defined by small angles, concentrations of edge dislocations, tapering fringes in sequences of layers, or strong image contrast. The outlined areas were enlarged to measure the packet thickness. The big arrows indicate the lengths of various smectite packets.