The usual material of the Assyrian ornamental metallurgy is bronze, composed of one part of tin to ten of copper which are exactly the proportions considered to be best by the Greeks and Romans, and still in ordinary use at the present day. In some instances, where more than common strength was required, as in the legs of tripods and tables, the bronze was ingeniously cast over an inner structure of iron. This practice was unknown to modern metallurgists until the discovery of the Assyrian specimens, from which it has been successfully imitated. We may presume that, besides bronze, the Assyrians used, to a certain extent, silver and gold as materials for ornamental metal-work. The earrings, bracelets, and armlets worn by the kings and the great officers of state were probably of the more valuable metal, while the similar ornaments worn by those of minor may have been of silver. [PLATE LXXVI., Fig. 3.] One solitary specimen only of either class has been found; but Mr. Layard discovered several moulds, with tasteful designs for earrings, both at Nimrud and at Koyunjik; and the sculptures show that both in these and the other personal ornaments a good deal of artistic excellence was exhibited. The earrings are frequent in the form of a cross, and are sometimes delicately chased. The armlets and bracelets generally terminate in the heads of rams or bulls, which seem to have been rendered with spirit and taste. [Illustration: PLATE 77] [Illustration: PLATE 78] By one or two instances it appears that the Assyrians knew how to inlay one metal with another. [PLATE LXXVI, Fig. 5.] The specimens discovered are scarcely of an artistic character, being merely winged scarabaei, outlined in gold on a bronze ground [PLATE LXXVI., Fig. 4.] The work, however, is delicate, and the form very much more true to nature than that which prevailed in Egypt.