| OUMNH Number: | 789 | 
|---|---|
| Name and quarry location: | probably porfido Trentino, from the Alps, and probably from the area of Bolzano, Trentino-Alto Adige, Italy | 
| Geological description: | Porphyritic rhyolite or dacite with phenocrysts of quartz, feldspar and biotite. | 
| Comments: | Comparison with a number of specimens of porphyry in the Naturhistorisches Museum Wien indicates this is probably from the Permian Atesino-Cima d'Asta volcanic complex of the Bolzano area, and is a variety of the stone known as porfido Trentino. | 
| References: | Andreolli (2003-4); Price (2007) 204 | 
| Further information: |  | 
| Corsi's classification: | Class 15. Porphyry; Species 1; ii. Italian porphyries | 
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| Corsi's text: | 195.1 Porfido delle Alpi | 
