selkein

Selkein is a fictional mineral described in speculative geology as a layered aluminosilicate with variable composition, typically containing aluminum, silicon, oxygen, and hydrogen, with iron or magnesium as impurities. It forms under metamorphic conditions and is named after a fictional Selka region where it was first identified.

In structure, selkein is described as consisting of silicate sheets with interlayer water, giving it a platy habit and a tendency to cleave. Its composition can vary, yielding a range of colors from pale green to gray and a vitreous to pearly luster. Typical physical properties reported in the literature include a Mohs hardness of about 4 to 5 and a density around 2.8 to 3.2 g/cm3. Selkein crystals are usually small and tabular, though botryoidal and fibrous forms are sometimes described in speculative field reports.

Occurrence and formation: selkein is reported from high-grade metamorphic rocks and pegmatites, often in association with quartz, biotite, and kyanite. It is thought to form during metamorphism involving the partial dehydration of aluminous silicate precursors, followed by interlayer hydration.

Uses and significance: because selkein is described only in theoretical contexts, it is not mined commercially. In speculative studies, its potential applications include refractory ceramics, ceramic glazes, and as a catalyst support material due to its thermal stability and surface properties.

See also: silicate minerals, aluminosilicates, metamorphic rocks.