singlemineral

Singlemineral, or monomineralic, describes a specimen, rock, or mass composed predominantly of a single mineral species. In practice, a sample is considered singlemineral when one mineral makes up the overwhelming majority of the material, with only minor accessory minerals or inclusions. The term distinguishes homogeneous material from polymineralic rocks that contain several minerals.

Monomineralic rocks occur in several settings. Quartzite, formed mainly from quartz, is a classic example. Marble and other calcite- or dolomite-dominated rocks are common monomineral types. Gypsum rocks like alabaster can also be monomineralic. In some cases, large individual crystals embedded in a host rock are studied as singlemineral specimens, even if the surrounding matrix hosts other minerals.

Identification relies on optical microscopy, X-ray diffraction, and electron probe analysis to confirm mineral identity and detect trace phases. Monomineralic materials provide pure diagnostic properties for optical mineralogy and are valued in industry where uniform mineralogy simplifies processing, such as quartz for glassmaking or high-purity calcite for fillers.

Formation pathways include crystallization from magma or hydrothermal fluids, and metamorphic recrystallization that favors a single phase. Studying singlemineral specimens aids in interpreting formation conditions and the geological history of a rock.