In the Neo-Babylonian period seals with names and dated impressions are virtually unknown. Therefore the chronology of Babylonian seals of the first half of the first millennium BC is very difficult to reconstruct. However certain features do allow us to identify seals as Babylonian. Hard stones were used much more extensively in Babylonia than in Assyria and the seal makers also achieved greater skill in cutting the designs using fine wheels and drills. The high, probably feathered, head-dress worn by the deities is a typical Babylonian feature, as is the duplication of figures, and the fact that the wings of four-winged figures are of equal length (on Assyrian seals, the upper pair of wings tend to be shorter). Other Babylonian features include the small animal (or here a human-headed winged lion) which appears in a contorted posture, and the presence of the small plant in a pot. It is probable that seal-cutters from Babylonia passed their skills on to Assyrian seal-cutters who, in their turn, produced such masterpieces as a green garnet seal showing Ishtar, also in the British Museum.