Corsi Collection of Decorative Stones

view of stone 794

Corsi 794, approx. 145 x 73 x 40 mm, © Oxford University Museum of Natural History

OUMNH Number: 794  
Name and quarry location: Porfido del'Elba, from the island of Elba, Livorno, Tuscany, Italy  
Geological description: Porphyritic andesite or trachyandesite. Subhedral phenocrysts of plagioclase and pyroxene in fine-grained reddish-brown groundmass, possibly devitrified glass. Curved alignment of crystals indicates viscous flow.  
Comments: This locality has not been confirmed, but may be correct.  
References:  
Further information:
 


Corsi's classification: Class 15. Porphyry; Species 1; ii. Italian porphyries  
Corsi's text: 196.6 Porfido dell'Elba  

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