Cf. D. Williams and J. M. Ogden, Greek Gold, The British Museum, London, 1994, p. 197, no. 131; and Cleopatra's Egypt: Age of the Ptolemies, The Brooklyn Museum, 1988, p. 196, no. 83, pl. XIX for a similar Herakles knot from the collection of Christos G. Bastis. The motif originated in Egyptian art and was later adopted by Alexander the Great and his successors as one of their insignia. "The significance of the square knot was ... transformed to conform to Greek sensibilities. It became the 'Herakles knot', whose ropes symbolized the union of Zeus and Rhea as snakes. The Greeks believed the knot to be imbued with amuletic properties particularly efficacious for healing wounds."