Figure 6.

Concentration of cations in these experiments versus in natural settings. Cation concentrations for (A) calcium, (B) magnesium, and (C) iron, observed to produce flocculation of lipid vesicles in this study far exceed the concentrations found in natural hot-spring settings [52]. Mass flocculation of lipid vesicles occurs beyond ~1.9 mM of Ca, Fe, and Mg cations in this study, while natural settings on Earth are observed to be <0.7 mM [52,69]. Natural hot-spring data are from Midway Geyser Basin, Norris Geyser Basin, Bison Pool, and Chocolate Pots in Yellowstone California; Hell’s Gate and Whangapipiro in New Zealand; and Kamchatka in Russia. Each site had a different relative abundance of cations in solution, with the highest Fe²⁺ at Chocolate Pots in Yellowstone [52,69].