Maturity chlorite

The effect is most marked in more mature sedimentary rocks where temperatures have been relatively high. The phenomenon represents not only the chloritization or kaolinitization of muscovite but also its illitization. 

Argillaceous Rocks. As a general rule, solid mineralogical criteria for the increasing degree of mineral maturity include (1) the transformation of montmorillonite to illite via a sequence of mixed-layer minerals of the montmorillonite-illite type, (2) the appearance of chlorite, and (3) the disappearance of potassic feldspars by decomposition. These mineral transformations may be described by the following reactions ... 

The rates of delignification of the cell walls of Lolium pererme and Trifolium pratense at different stages of maturity have been determined after treatment with sodium chlorite. If the lignin content was less than 10%, delignification... 

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