c89a5c28_mical_Sediments_and_Landscapes__1
[0] Clay Minerals [2] Clay minerals are not important, and hence there is no reason why they should dominate in varnish. [3] Clay minerals are critical to this model, and the model explains their dominance. Mn mobilized from bacteria fit into octahedral positions, cementing clays. [4] Proponents assert that clay minerals are not important, and hence there is no reason why they should dominate in varnish. [1] 
Clay minerals are not important, and hence there is no reason why they should dominate in varnish.
Rock Varnish Chapter 8 in Geochemical Sediments and Landscapes
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