(Quistiav, Guern, Pontivy, Morbihan, Bretagne, France)
Quartz-pitchblende vein in granite, near Quistiav hamlet, WSW of Guern.
Two generations of quartz :
- Early palissadic quartz, smokey or hematized quartz
- Cryptocrystalline quartz with fragments of early pitchblende and spherolites of secondary pitchblende. This quartz contains the sulphide mineralization