Dissolution of unstable framework grains such as feldspar and rock fragments (including chert) is common in sandstones worldwide. Such framework dissolution usually results in a depletion of unstable framework grains and a corresponding enrichment of quartz. Failure to recognize this diagenetic modification of composition of a sandstone will result in misinterpretation of its provenance. A proper evaluation of sandstone composition may be achieved by including the dissolved portion of a framework grain as a grain, rather than as porosity, while point counting. This should be useful in interpreting original composition of sandstones and their provenance.

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