Mylonite is a fine-grained, compact rock produced by dynamic recrystallization of the constituent minerals resulting in a reduction of the grain size of the rock.
en.wikipedia.org Modal metasomatism may result in formation of amphibole and phlogopite, and the presence of these minerals in peridotite xenoliths has been considered strong evidence of metasomatic processes in the mantle.
en.wikipedia.org Minerals that typically form nodules include calcite, chert, apatite (phosphorite), anhydrite, and pyrite.
en.wikipedia.org Much of the sand colors stem from the rich content of minerals in the sand, such as rutile, ilmenite, zircon, and monazite.
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