Opal (variety hyalite), Chalcedony and Quartz - Monok, Zemplén Mountains, Hungary - 63 mm x 52 mm x 50 mm
Mineral: Opal (variety hyalite), Chalcedony and Quartz
Locality: Monok, Zemplén Mountains, Szerencs District, Borsod-Abaúj-Zemplén, Hungary
Dimensions: 63 mm x 52 mm x 50 mm

Description: The hyalite becomes very green in every type of UV light.