c89a5c28_mical_Sediments_and_Landscapes__1
[0] Mn-mineralogy [2] Mn-mineralogy is consistent with biotic enhancement of Mn. [3] This model explains the fit of nanometer-scale Mn-oxides into clay minerals, with detailed HRTEM observations supporting earlier hypotheses (Potter, 1979: 174-175; Potter and Rossman, 1977). [4] Mn-mineralogy is not explained. [1] 
Mn-mineralogy is not explained.
Rock Varnish Chapter 8 in Geochemical Sediments and Landscapes
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