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Greywacke

116 is a good example of a greywacke, with abundant fine-grained matrix between the grains (brownish-grey in illustration). It is poorly-sorted and most of thc grains are quartz. Therc are, however, some rock fragments (e.g. rounded grain, upper left) which makes this a lithic greywacke according to the classifica-tion on page 109.