In studies related to the origin of life on Earth, the authors considered the geochem. conditions for the formation of tetrose-, pentose-, and hexose phosphates in the Archean. Some of the reactions depend on bilateral surface active minerals for concn. and induction. One such mineral is ferroferric hydroxide (green rust), which is a likely predecessor of sedimentary magnetite, a major component of Archean banded iron formations. Such iron formations host the oldest known traces of life on Earth according ti S. J. Mojzsis et al. (1996). [on SciFinder (R)]