berüül
Berüül is a fictional mineral described in speculative geology and science fiction literature. It is notable for its translucent to transparent body and a vivid iridescent sheen that shifts from blue to green under different lighting. The mineral commonly shows strong pleochroism and a faint halo of luminescence when exposed to ultraviolet light.
The name berüül was coined in the mid-22nd century by researchers working in the Hyrren Basin, and
Berüül typically occurs as prismatic to tabular crystals, though large masses are uncommon. Mohs hardness is
Berüül forms in late-stage granitic pegmatites and hydrothermal veins, often associated with quartz, feldspar, and topaz.
In fiction, berüül is prized as a gemstone for jewelry and ornamental carvings, and is studied for