Macroscopic: Pale pinkish colour with sporadic red and less white inclusions. Smooth/even break.
Petrographic: 1-3% inclusions, <1.66mm. Kaolinitic clay matrix, optically highly active. Fine-grained clay paste containing most distinctively sporadically larger fragments of reddish-brown shale (high optical density, sharp boundaries). As accessories, quartz, chert and volcanic rock fragments of basaltic composition are attested. Fine inclusions comprise clinopyroxene/augite and kaolinitic clay pellets.
This is a relatively pure kaolinitic clay most likely relating to shale or Nubian sandstone formations rather than to granite in the Aswan region. Appropriate environmental conditions for the formation of such clays are known from Aswan’s West bank and the area northeast of the modern city. The clay paste corresponds to Petrofabric ASW-PC_04 described by Peloschek 2015, 105 and had been used most extensively in the first century AD. Analysed samples originate from the excavations in Syene.
