This unusual pottery vessel is in the shape of an ostrich egg. It is evidence that the trade in ostrich eggs went back to the Middle Minoan period, since the known examples imported to the Aegean come from the Late Bronze Age.
Bibliography
Evans, Arthur. 1921. The Palace of Minos at Knossos, I, pp. 594-595, fig. 436a
Myres, John (ed.). 1936. British Archaeological Discoveries in Greece and Crete 1886-1936, p. 16