paraatit

Paraatit are a proposed family of layered silicate minerals characterized by sheet-like structures and hydration between layers. The term paraatit was coined to describe minerals with this distinctive layered arrangement and variable interlayer cations. They commonly appear as thin, tabular grains with basal cleavage and a vitreous to pearly luster.

Chemically, paraatit are generally hydrated aluminosilicates that incorporate interlayer water and exchangeable cations such as sodium, potassium, calcium, or magnesium. Their color ranges from pale yellow to greenish gray, and their habit often yields a light, translucent appearance in thin sections. The interlayer region and hydration state are key features used to distinguish paraatit from related phyllosilicate groups.

Paraatit form in metamorphic and hydrothermal environments where aluminous rocks interact with silicate-rich fluids. They are especially associated with zones of contact metamorphism and, in some settings, subduction-related belts. Common mineral companions include micas, clays, zeolites, and chlorite, reflecting their formation under low- to moderate-temperature conditions with active fluid phases.

In research contexts, paraatit are of interest for their potential ion-exchange properties and as components in lightweight ceramic composites. Their platy morphology and layered structure also make them relevant to studies of mineral stability under changing hydration and temperature conditions. Ongoing work in crystallography and solid-state chemistry aims to refine crystal-structure models and to clarify the range of compositions that fall within the paraatit group.