Magic of transparency

Scorching flames shoot out from a furnace heating silica (pure sand) to 1,300°C, to create a material that is malleable when hot, and hard, impermeable, smooth and transparent when cooled—the wonders of glass synthesis!

Glass's initial applications date from the end of prehistory and were mostly decorative, such as jewelry and flasks. During the Roman Empire, the first greenhouses gave Tiberius cucumbers to eat throughout the year: they marked the invention of window glass, which lets us keep in the heat of home fires while enjoying the sun's light. The optical properties of glass led to fascinating discoveries such as mirrors, magnifying glasses and prisms, which break light down into the color spectrum.