silex

Latin silex meant flint, the hard, glassy stone that fractures into sharp edges. For a hundred thousand years before any Latin speaker existed, hominids had been knapping silex into tools, arrowheads, and fire-starters. The Romans used the word for any hard stone, but its core meaning was always the same: the rock you can split and shape, the rock that makes sparks.

In 1824, the Swedish chemist Jöns Jacob Berzelius isolated a new element from silica, the oxide of flint. He named it silicium, from silex. The English form silicon appeared shortly after, dropping the Latinate ending. For over a century, the element was mainly of interest to geologists and glassmakers. Silicon dioxide is quartz. It is sand. It is the most abundant compound in the Earth's crust.

Everything changed in 1947 at Bell Labs in Murray Hill, New Jersey. William Shockley, John Bardeen, and Walter Brattain built the first practical transistor using germanium, but silicon quickly proved superior. By the 1960s, silicon wafers were the substrate of every integrated circuit. In 1971, journalist Don Hoefler coined Silicon Valley in a series of articles for Electronic News, naming the stretch of Santa Clara County where Fairchild Semiconductor and Intel had set up shop.

The progression is almost too neat. A Neolithic toolmaker chips flint to make a cutting edge. A Bronze Age smelter uses flint to strike fire. A 19th-century chemist isolates the element inside the stone. A 20th-century physicist etches circuits onto wafers of the purified element. The material never changed. Only the scale of what humans could do with it shrank, from hand-sized blades to transistors measured in nanometers.