Heliandureid

Heliandureid is a fictional mineral described in speculative geology and science fiction contexts. The name combines helios, the sun, and a suffix evocative of mineral classifications, reflecting its imagined formation in sun-exposed hydrothermal environments.

It is depicted as a rare metallic sulfide with a general formula such as (Fe,Ni,Cu)S2 and a hexagonal crystal system. In typical depictions, grains are sub-millimeter in size and exhibit a brassy to bronze color with a metallic luster. Physical properties are often stated as Mohs hardness around 4–5 and a density near 4.6–5.2 g/cm3. The mineral is described as opaque with weak magnetic behavior and, in some narratives, exhibits luminescence under ultraviolet light.

Occurrence and formation are described within fictional settings as taking place in high-temperature, reducing hydrothermal veins in sun-rich regions, for example a geologically active area called the Helian Belt. In these stories heliandureid is frequently associated with minerals such as pyrrhotite, chalcopyrite, and pentlandite, forming through processes influenced by intense irradiation and unique redox conditions.

Applications and significance within its fictional world include potential use as a sunlight-absorbing material for hypothetical photovoltaic systems and as a source of luminescent markers or specialty metals. Its presumed abundance in certain extraterrestrial or rapidly irradiated crusts provides material for world-building and economic speculation in the narratives where it appears.

Discovery and naming are attributed to a fictional mineralogist, Dr. A. Lumen, in 2145. It is important to note that heliandureid is not recognized by real-world mineral databases or scientific authorities, and it remains a construct for storytelling and hypothetical discussion.