The Ffestiniog region contains five major slate veins, which are on top of a thick layer of feldspathic porphyry, called the "Glanypwll Trap".
Penrhyn Quarry | Headington Quarry | Quarry Bank Mill | Gurney Slade quarry | Walcott Quarry | ''Untitled'' (1961), sculpture by Auguste Cardenas in the area above the Roman quarry in Sankt Margarethen im Burgenland | Seneca Quarry | Rosemanowes Quarry | Public Quarry at Government Island | Penrhyn Quarry | Nelson's Ledges Quarry Park | Lulsgate Quarry | '''Lithiophilite''', well-defined crystals to 3 cm, stacked en echelon in matrix. Locality: Emmons Quarry, Uncle Tom Mtn. Greenwood, Maine | Jerry Quarry | Dry Mesa Quarry | Cann Quarry Canal | Bobby Quarry | Blumenberg (quarry) | Bellwood Quarry |