Slegilwith

Slegilwith is a fictional mineral described for illustrative purposes in this article. It is characterized by a translucent to submetallic body with an iridescent surface sheen that becomes more vivid in polished specimens. Mineralogically, it is classified as a silicate and is typically formed within high-grade metamorphic rocks as small prismatic crystals. Its color can range from dark gray to steel blue, with a subtle play of color caused by internal inclusions and microstructural variation.

Discovery and naming: The term slegilwith was coined in reference to the fictional Slegil Mountains, where the mineral was first described by the geologist Mina Kraul in 1923. The name derives from the local term slegil, meaning shimmer, plus the suffix -with to denote a mineral substance.

Physical properties: Slegilwith is relatively hard and resistant to weathering, with a Mohs hardness commonly reported around 6 to 7 and a density around 3.2 to 3.6 g/cm3. Chemical analyses indicate a silicate framework enriched with iron and titanium, and the mineral displays limited cleavage, favoring fracture surfaces that reveal its iridescent interior.

Occurrence and uses: In the fictional record, slegilwith is found in narrow veins within remote metamorphic belts in the Nordmarch and Valissia regions. It is mainly used as a decorative stone and collector’s mineral, with minor demand in experimental optics due to its iridescence. Researchers study its crystallography and potential synthetic reproduction.

Further reading: See the glossary of fictional minerals.