Corsi Collection of Decorative Stones

view of stone 720

Corsi 720, approx. 145 x 73 x 40 mm, © Oxford University Museum of Natural History

OUMNH Number: 720  
Name and quarry location: 'Aventurine' (ferruginous sandstone), perhaps from Gebel Ahmar, Cairo or Gebels Gulab or Tingar, Aswan, all in the Nile Valley, Egypt  
Geological description: Orthoquartzite; a poorly sorted coarse siliceous sandstone/fine conglomerate with goethite coating grains and a silica cement.  
Comments: This stone may come from Roman quarries in the Nile Valley, Egypt: either from a quarry on Gebel Ahmar, Cairo in the Oligocene Gebel Ahmar Formation; or from quarries on Gebels Gulab and Tingar, near the ruins of St Simon’s Monastery on the west bank opposite Aswan, both in the Upper Cretaceous Umm Barmil Formation. (J. Harrell, pers. comm.). There is no sparkle to this specimen so it would not today be called aventurine.  
References: Corsi (1845) 253-254; Harrell (2010a)  
Further information:
 


Corsi's classification: Class 14. Quartz and its varieties; Species 4. Aventurine  
Corsi's text: 181.1 Avventurine  

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