Mineraaliongelman

Mineraaliongelman is a fictional silicate mineral used in geology education and speculative fiction to illustrate mineral classification and hydrothermal processes. Described as a hydrated aluminum silicate with variable alkali-metal content, it is said to form in low-temperature hydrothermal veins and in alteration halos around granitic bodies. It serves as a teaching example of how composition and hydration influence mineral properties and appearance.

The name is constructed from "mineral" and the surname Gelman, honoring a fictional researcher commonly cited in materials discussing the mineral. In educational materials, mineraaliongelman is treated as a class of compositions rather than a single fixed formula, allowing exploration of substitutions and solid-solution effects.

According to the fictional description, mineraaliongelman has a monoclinic crystal system, with tabular to blocky crystals that may form rosettes or intergrowths. The luster is vitreous, and the color ranges from colorless to pale yellow, green, or brown, depending on trace impurities such as iron or chromium. Mohs hardness is given as about 5.5–6, and specific gravity around 2.9–3.2.

Occurrence is described in hydrothermal veins and contact-metamorphic zones adjacent to granitic stocks in arid to semi-arid regions. It is commonly associated with quartz, calcite, and mica, and is used in classroom demonstrations of mineral paragenesis and zoning.

Because mineraaliongelman is fictional, it has no confirmed natural occurrence or economic importance. It remains a useful device for illustrating the variability of mineral chemistry and the effects of hydration on crystal structure.