The Iron Age is the final epoch of the three historical Metal Ages, after the Copper Age and Bronze Age. It has also been considered as the final age of the three-age division starting with prehistory and progressing to protohistory. In this usage, it is preceded by the Stone Age and Bronze Age. These concepts originated for describing Iron Age Europe and the ancient Near East. In the archaeology of the Americas, a five-period system is conventionally used instead; indigenous cultures there did not develop an iron economy in the pre-Columbian era, though some did work copper and silver. Indigenous metalworking arrived in Australia with European contact. Although meteoric iron has been used for millennia in many regions, the beginning of the Iron Age is defined locally around the world by archaeological convention when the production of smelted iron replaces their bronze equivalents in common use. However, this notion is being challenged.