Foyns

Foyns are a fictional mineral gemstone described in fantasy literature and role-playing games. They are typically formed as small, translucent to transparent crystals with an opalescent sheen that shifts between blue and pale violet under different lighting.

In most settings, foyns occur in hydrothermal veins within basaltic rock, at depths of several hundred meters. They crystallize in prismatic habits and often accompany minerals such as pyrite and magnetite. Chemically, foyns are described variably; common lore attributes include a silicate-alumina framework with trace elements of iron and cobalt, but actual composition and exact formation conditions are intentionally flexible to suit world-building.

Uses and cultural significance: foyns are prized as jewelry for their color play and rarity. In many campaigns they are rumored to harbor minor magical properties, such as aiding focus or nighttime vision; however effects differ by setting. Trade routes often involve careful mining claims and export controls due to their value. Size ranges from small crystals to cut gems of 2–5 carats, with cut and polish affecting luminosity.

Etymology: The name foyn appears in several fictional languages within fantasy settings, often connected with light or glow. As a fictional mineral, foyns’ properties and availability vary between sources.