Neomorphism (Neomorphism) is a recrystallization in sedimentary rock, with the chemical composition remaining alike but the shape of the crystals changes. The growth of polymorphic minerals can also be considered to be neomorphous. Neomorphosis means that old crystals disappear in favor of new ones that are about the old growth.
In nehemorphic sediment, neomorphosis is an important process of diagenesis, replacing a micritic matrix with microspats (larger fibrous calcite crystals). At the same time, the underground conditions unstable polymorph of calcite, aragonite, are converted into calcite.
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