Keturios

Keturios is a fictional mineral concept used in speculative geology and science fiction. It does not have a basis in real-world mineralogy, but is employed in worldbuilding to explore materials science at extreme conditions.

In imagined settings, keturios is described as a dense crystal that crystallizes in the hexagonal system. It typically appears with a glassy to vitreous luster and can show color variation from electric blue to violet. Reported hardness is high, often placed around 7.5 on the Mohs scale, and it can exhibit luminescence under ultraviolet light.

The speculative chemistry often notes keturios as a silicate-oxide phase enriched with alkali metals and rare earth elements, forming complex, dehydrated structures that resist degradation at high temperatures. Its exact composition varies with the fictional environment.

Formation and occurrence in narratives are linked to extreme planetary interiors, subduction analogs, or rapid quenching in cryogenic volcanic plumes. Keturios is sometimes described as forming in metasomatic rims around tectonic ridges on ocean worlds.

Proposed applications in fiction include high-temperature ceramics, superconducting or photonic devices, and lightweight heat shields. Its luminescent properties are often used for signaling or as a visual indicator of high-temperature processing in worldbuilding.

In scholarship and fan communities, keturios serves as a generic placeholder mineral, useful for illustrating material constraints and the interplay between geology and technology. Because it is fictional, its properties and uses vary between works.