PORTUGAL: Steel is considered by many one of the great Industrial Age inventions, but it turns out some inhabitants of Iberia were capable of forging tempered steel tools 2,900 years ago. Metallographic analysis of a chisel from Rocha do Vigio determined that it is made of carbon-rich steel. This durable material was needed to carve stone stelas featuring complex anthropomorphic and geometric motifs, because the local silicated quartz sandstone was much too hard for stone, bronze, or iron chisels.