Hyalite AKA Muller’s glass, Water Opal, and Jalite, Opal-AN
Locality: Kopasz Hill andesite quarry, Tarcal, Tokaj District, Borsod-Abaúj-Zemplén County, Hungary
Formula: SiO2 · nH2O
Fluorescence captured under short-wave UV.
Hyalite is a transparent form of opal with a glassy lustre. It may exhibit an internal play of colors if natural inclusions are present.