quartzitic

Quartzitic is an adjective used in geology and related fields to describe rocks, textures, or assemblages in which quartz is the dominant mineral. It is most often applied to quartz-rich sandstones and to quartz-rich metamorphic rocks such as quartzite. A quartzitic sandstone, for example, contains a high proportion of quartz grains with limited feldspar or lithic fragments and commonly exhibits silica cement that binds the grains into a hard, dense rock. In metamorphic rocks, the term describes rocks in which quartz constitutes the principal framework mineral, often forming an interlocking mosaic as seen in quartzite.

Porosity in quartzitic sandstones tends to be lower than in more feldspathic counterparts due to silica cementation, though porosity can be preserved in framework- or carbonate-cemented varieties. The presence of quartz as the predominant mineral is commonly interpreted as indicating a mature, silica-rich sediment source or extensive diagenetic silica overgrowth.

Quartzitic textures can inform provenance studies, diagenetic history, and weathering resistance. The term is distinct from quartzite, which refers specifically to the metamorphosed quartz-rich sandstone, and from quartz sands that are simply high in quartz but not yet lithified as quartzite.