Jernsulfur

Jernsulfur is a term found in speculative geology and science fiction used to denote an iron sulfide phase with variable composition. It is not an officially recognized mineral by major mineralogical authorities, and there is no formal description in current mineral databases.

Etymology: The name combines jern, a root meaning iron in several Germanic languages, with sulfur.

Composition and structure: In discussions, jernsulfur refers to a family of iron sulfide phases with Fe:S ratios spanning roughly from FeS to FeS2, often non-stoichiometric (Fe1−xS) and with lamellar or granular microstructures. Its precise crystallography is left undefined in fictional and provisional uses.

Physical properties: Reported properties vary by imagined variant, but typical portrayals assign a metallic luster, opaque appearance, and color ranging from dark gray to bronze. Hardness is described between 3 and 6 on the Mohs scale, with a metallic streak. Because it is iron-rich, magnetism is commonly noted in speculative depictions.

Occurrence and formation: In speculative contexts, jernsulfur is said to form in reducing, sulfur-rich environments, such as hypothetical hydrothermal vent systems or magmatic sulfide pods. There is no confirmed natural occurrence in real-world geology.

Uses and significance: Primarily a concept for thought experiments, world-building, or fiction; any industrial use or large-scale extraction would be hypothetical.

See also: Pyrite, Pyrrhotite, Iron sulfide, Sulfide minerals.