Explore how precious gems, metals and energy resources are forged under extraordinary circumstances deep within the Earth, and discover how their unique properties have helped lift humanity from the Stone Age to the stars. Explore how precious gems, metals, and energy resources are forged under extraordinary circumstances deep within the Earth, and discover how their unique properties have helped lift humanity from the Stone Age to the stars. The enduring luster of gold, the conductivity of copper, the strength of steel—the unique properties of metals have reshaped societies and defined eras; they have such an essential role in human history that entire ages have been named after them. But what gives metals their astounding characteristics? From the perfect ring of a bronze bell to the awe-striking steel construction of Beijing's "Bird's Nest" stadium, how have humans perfected metalworking? And how have metals enabled our modern hi-tech world? Explore the science of metals with chemists and engineers as they literally test the mettle of metals and investigate how these remarkable materials have ushered humanity from the Stone Age to the stars.