FIG. 15.

Comparison of bending (x axis) versus number of direction changes (y axis) for HFO filaments, cryptic filaments, microbial filaments, and mineral fibers. Microbial filaments, some cryptic filaments, and many HFO filaments exhibit high values in bending and number of direction changes. This demonstrates flexibility and is consistent with morphology parameters for biogenic filaments (Hofmann et al., 2008). Although some HFO filaments can exhibit lower values in bending and number of direction changes, microbial filaments in the gossan exhibit generally similar values, suggesting that the HFO filaments are mineral-coated microbial filaments. (Color graphics available at www.liebertonline.com/ast)