Corsi Collection of Decorative Stones

view of stone 650

Corsi 650, approx. 145 x 73 x 40 mm, © Oxford University Museum of Natural History

OUMNH Number: 650  
Name and quarry location: Pietra dell'Etna, from Mt. Etna, Catania, Sicily, Italy  
Geological description: An altered crystal-rich ignimbrite. Amygdaloidal microporphyritic rock clasts with altered subhedral phenocrysts of a ferromagnesian mineral and feldspar, are set in very fine-grained dark matrix. Amygdales are rounded or irregular in shape, and many contain carbonate infills which have a banded agate-like appearance. The streaky appearance of paler patches suggests a flattened shard structure.  
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Corsi's classification: Class 8. Volcanic stones; ii. Stones from Etna  
Corsi's text: 156.6 Pietra dell'Etna  

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