Askelein

Askelein is a fictional mineral frequently referenced in fantasy literature, tabletop role-playing games, and speculative geology. The name is usually traced to imagined linguistic roots meaning ash-like, reflecting its characteristic ash-gray to pale blue-gray color.

Description and properties: Askelein forms translucent to transparent crystals with a vitreous luster. It commonly occurs as prismatic crystals or granular aggregates and has a hardness around 5.5 to 6 on the Mohs scale. In world-building classifications it crystallizes in a tetragonal system. Its composition is described as a mixed aluminum-iron silicate, often represented conceptually as (Al,Fe)2(SiO4)3, with the exact iron content and trace elements varying by locality.

Occurrence: In fictional geologies, askelein forms in high-temperature hydrothermal veins within basaltic or andesitic rocks, typically near volcanic districts. It is commonly found alongside magnetite, olivine, and hornblende in these settings.

Uses: Askelein is valued for its subdued color and perceived heat stability. In many settings it is used as a gemstone or decorative material, and in some worlds it is incorporated into magical sigils or experimental devices where temperature resistance is advantageous.

History and etymology: The term askelein appears in in-universe mineral catalogs and lore from various eras. The name has been standard in fantasy catalogs since medieval-inspired periods of those fictional worlds. See also: list of minerals, silicate minerals.