Revelation lists iron among the trade goods whose market collapses with Babylon's fall (18:12). Throughout Scripture, iron represents strength, durability, and sometimes oppression (iron yoke, iron furnace). Ancient metallurgy made iron valuable for agricultural implements, weapons, and construction. The inclusion of both precious metals (gold, silver) and utilitarian iron in Babylon's cargo shows the comprehensive scope of its commerce. Iron also appears symbolically in Revelation's visions: the rod of iron with which Christ rules (2:27, 12:5, 19:15) denotes unbreakable authority.