Stará Paka.

A large abandoned shelf quarry opened in olivine basalts to basaltic andesites (melaphyres) with a face over 20 m high and 270 m long. Amygdaloidal and massive andesitoids alternate with intervals of reddish-brown tuffs and tuffites. Lavas and pyroclastics exposed by the quarry pertain to the Levín Volcanic Field produced by basic eruptive and effusive activity in the Permian. The upper pyroclastic interval in the Hvězda Quarry rests upon a deeply jointed surface of melaphyre up to 10 m thick. Joints in melaphyre, as much as 1 m deep in places, are filled with fine-grained tuff with accretion lapilli. Finds of volcanic bombs up to 30 cm in size have been also reported. The amygdules in melaphyre vary between several millimetres and tens of centimetres in size, with the vesicles being often filled with chalcedony, varicoloured agates and other minerals.




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