Eisitovan

Eisitovan is a hypothetical mineral described in theoretical crystallography and computational mineralogy. The term is used in educational simulations and speculative literature to illustrate possible high‑pressure silicate phases and polymorphism in the Earth's mantle. In proposed models, eisitovan is a dense, crystalline silicate that can host iron and aluminum substitutions within a layered framework.

Physical and structural properties described in models include a monoclinic crystal system, a vitreous to sub‑vitreous luster, and a color range from pale blue to gray. Reported hardness is about 6.0–6.5 on the Mohs scale, with two cleavage directions near perpendicular, and a theoretical density in the roughly 3.2–3.5 g/cm3 range. It is commonly described as forming acicular or short-prismatic crystals in simulated HPHT environments.

Occurrence and formation: eisitovan is predicted to occur under high‑pressure, high‑temperature conditions analogous to subduction zones, and is studied primarily in laboratory HPHT experiments and computational phase‑stability analyses. No natural specimen has been confirmed to date.

Etymology and naming: the name eisitovan is a constructed term coined for these hypothetical phases, with etymological elements drawn from fictional or neutral roots. The designation is intended to be neutral and non‑geographically specific.

Research status and significance: eisitovan serves as a test case for crystallographic modeling, phase transitions in silicates, and mantle‑related geophysics simulations. If observed, it could illuminate pathways of polymorphism and help constrain structural responses under extreme conditions.