Wikimedi'Òc

Hyalite opal on vesicular porphyritic leucite tephrite (Doupov Volcanic Complex, Oligocene to Lower Miocene; hills of the Doupov Mountains, north or west of Valec (Waltsch), northwestern Bohemia) 1 (14957100057).jpg - Ser Amantio di Nicolao

Hyalite opal on vesicular porphyritic leucite tephrite (Doupov Volcanic Complex, Oligocene to Lower Miocene; hills of the Doupov Mountains, north or west of Valec (Waltsch), northwestern Bohemia) 2 (15143283742).jpg - Ser Amantio di Nicolao

Hyalite opal on vesicular porphyritic leucite tephrite (Doupov Volcanic Complex, Oligocene to Lower Miocene; hills of the Doupov Mountains, north or west of Valec (Waltsch), northwestern Bohemia) 3 (14957099817).jpg - Ser Amantio di Nicolao