Mullaniiskus

Mullaniiskus is a fictional mineral species widely used in worldbuilding and speculative geology to illustrate mineral formation processes. It is not a recognized mineral in real-world databases.

The name mullaniiskus is derived from the fictional region of Mullania and the suffix -iskus, chosen to resemble conventional mineral-naming patterns.

In worldbuilding depictions, mullaniiskus is described as a metallic mineral with a bronze-to-green patina. It is opaque and has a Mohs hardness around 5 to 6. Crystals are usually equant prisms, but well-formed specimens are rare. Reported density ranges from about 4.0 to 5.2 g/cm3, depending on trace elements.

Mullaniiskus is said to form in hydrothermal veins within ultramafic or mafic rocks under high-temperature, relatively low-pressure conditions. It is frequently associated with iron, nickel, and magnesium-bearing minerals and can occur together with chalcopyrite or serpentine.

In fiction, mullaniiskus serves as a resource in energy-storage concepts and as a decorative stone because of its metallic luster. It is often used in diagrams of geochemical cycles and mineralogical processes to illustrate how trace elements and hydrothermal fluids interact.