Purportedly found in North Saqqara, this is a rare and complete example of a rock crystal vessel from Egypt. A similar vessel is at the Fitzwilliam Museum, Cambridge (accession no. E.43.1912).
The ancient Egyptians sourced rock crystal in the areas of the Fayum and Bahariya in the Western desert, as well as the Sinai. Rock crystal vessels are exceptionally rare, probably due to the hardness of the material which makes it much more difficult to work. However, such practical motives did not determine the choice of material, but rather the purpose for which a vessel was intended. A much prized material throughout antiquity, the philosopher Pliny the Elder reported that the Romans favoured rock crystal not only for its sparkling brillance, but also for its cooling properties (cf. B Musche and J. Kröger, "Rock crystal", Encyclopaedia Iranica, Vol. VI, Fasc. 4, pp. 436-441).
For a discussion on the shape, cf. A. El-Khouli, Egyptian Stone Vessels, vol. I, Mainz, 1978, pp. 380-382.