Corsi Collection of Decorative Stones

view of stone 812

Corsi 812, approx. 145 x 73 x 40 mm, © Oxford University Museum of Natural History

OUMNH Number: 812  
Name and quarry location: Porfido delle Alpi, from the Alps; or perhaps from the island of Elba, Livorno, Tuscany, Italy  
Geological description: A microgabbro with a gabbro pegmatite containing large phenocrysts of white plagioclase feldspar. Altered, the pyroxene crystals are probably 'uralitised' to amphibole.  
Comments: A very similar specimen seen in a private collection is labelled as coming from the island of Elba, certainly a possible source of this stone.  
References:  
Further information:
 


Corsi's classification: Class 15. Porphyry; Species 2. Porphyries (Lacedaemon); ii. Italian 'serpentine' porphyry  
Corsi's text: 201.3 Serpentino delle Alpi  

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