The head was of fine gold. Its chest and arms were silver. Its abdomen and thighs were bronze. Its lower legs were iron, and its feet were a combination of iron and clay. Archaeologists have discovered similar images made of several types of precious metals in Babylonia. [1][source]
Several features are noteworthy. First, the head is the only member of the body made of only one metal. All the other parts had more than one substance with the exception of the arms. For example, the upper torso was silver but bronze lower down. The same was true of the legs and feet. Second, there is a consistently decreasing value to the substances beginning at the top and proceeding to the bottom of the image. Third, the image was top-heavy. The specific gravity of gold is about19 , silver about11 , brass about85 , and iron78. [2] Fourth, the substances progress from the softest to the hardest, top to bottom. The feet are a non-adhering combination of very hard and hard but fragile materials. The clay in view may have been baked clay that the Babylonians used as tiles in construction projects. [source][source][source]
Nebuchadnezzar"s Dream StatueHeadGoldValuableSoftSelf-contained unitHeavySmallestChest & armsSilverLess valuableHarder1unit & 2partsLighterLargerAbdomen& thighsBronzeEven less valuableEven harder1unit & 2different partsEven lighterEven largerLower legsIronStill less valuableStill harder2partsStill lighterStill largerFeet & toesIron & clayLeast valuableVery hard and very soft2parts & 10 segmentsLightestLargest[source]