c89a5c28_mical_Sediments_and_Landscapes__1
[0] Mn Enhancement [2] Abundant culturing research documents the presence of Mn-oxidizing organisms. [3] This model explicitly explains Mn enhancement, followed by clay cementation. [4] Mn enhancement is not explained by silica dissolution or reprecipitation. [1] 
This model was developed to explain Mn enhancement.
Rock Varnish Chapter 8 in Geochemical Sediments and Landscapes
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