Further work on the importance of nanobacteria in geology by R. L. Folk and co-workers includes study of calcium carbonate Bahama ooids, silicate clay minerals, metal sulfides, and iron oxides. In all these chemically diverse minerals, the putative nanobacteria are approximately the same size, mainly 0.05 to 0.2 μm. This suggests a commonality of origin. At least for the type locality at Viterbo, Italy, the biogenicity of these minute cells has been supported by transmission electron microscopy (TEM). Slices through a green bioslime showed entities from 0.4 down to as small as 0.09 μm with definite cell walls and interior dots resembling ribosomes; and even smaller objects with cell walls and interiors with diameters of 0.05 μm. Culturable organisms on earth are the same 0.05 μm size as the supposed nanobacteria on Mars.