Petrographic analysis of pottery from Naki Saleh and Sheik Muhsein in Southern Sinai fully corroborates the outward resemblance between this pottery and that from Arad. This is striking if it is borne in mind that Arad is situated in a sedimentary terrain, where no igneous rocks are found while the Sinai sites are situated in the heart of a preCambrian crystalline complex where no sedimentary rocks are present. Five petrographical groups have been distinguished in the analysis of 35 samples. (Address of first author: Tel Aviv Univ., Tel Aviv, Israel.) -- AATA