nephelinic

Nephelinic is an adjective used primarily in geology and mineralogy to describe materials, properties, or occurrences related to nepheline or to nephelinite-derived rock assemblages. Nepheline is a tectosilicate mineral in the feldspathoid group, commonly found in silica-undersaturated rocks. The term is not widely used outside specialist literature and may vary in definition between sources.

Etymology and linguistic note: Nephelinic derives from the noun nepheline, which in turn comes from the Greek nephelē meaning “cloud.” The suffix -inic is a standard form in geology for forming adjectives that relate to a root mineral or rock type, yielding nephelinic to indicate a relationship to nepheline or nephelinite contexts.

Usage and context: In petrology, nephelinic is used to describe rocks or minerals in which nepheline is a dominant or significant component, or to denote textures, mineral assemblages, or chemical compositions that emphasize nepheline-bearing relationships. The term may appear in discussions of silica-undersaturated rocks, feldspathoid-bearing rocks, or nephelinite-type magmatism. Because it is a niche term, precise usage can vary, and some authors may prefer phrasing such as “nepheline-bearing” or “nephelinite-related.”

See also: Nepheline, Nephelinite, Feldspathoid, Silica-undersaturated rocks.

Notes: Nephelinic terminology is specialized and not universally standardized across all mineralogical references. When encountered, it is usually best interpreted in the context of nepheline-related petrology or mineralogy.