Silicon

Silicon was first prepared as an element by Jons Jacob Berzelius in 1824, though its ubiquitous oxide, silica, is one of the commonest substances on Earth. The name comes from the Latin silex, silicis, meaning flint, with the -on ending that marks it as kin to carbon and boron rather than the -ium of a typical metal, reflecting its status as a metalloid. Silicon is the second most abundant element in the crust after oxygen, the backbone of rocks, sand and glass. Purified to extraordinary perfection, silicon is the semiconductor from which almost all electronic chips are made, so that this ordinary constituent of stone underpins the entire digital age; its compounds also form glass, cement, and the flexible silicone polymers.

Quartz, silicon's commonest crystalline form, carried its own beliefs long before the element inside it was known: Pliny the Elder recorded the ancient idea that rock crystal was water or ice frozen so hard by extreme cold that it could never thaw, a belief that lent the stone an aura of purity. In the twentieth century quartz acquired a new pseudoscientific life in the New Age crystal healing movement, which claims that quartz and other silica-based stones channel or amplify spiritual energy, a claim with no basis in the element's well understood physical chemistry. Silicon's genuine modern power is electronic rather than mystical: its crystal structure, not any energy it channels, is what makes it the substrate of the semiconductor industry.

Through its parent word flint, silicon reaches back to the oldest human technology: the knapped flint tools and fire-strikers of the Stone Age are worked silica, and quartz, agate, jasper and opal, stones long carried for ornament and charm, are all forms of the same oxide. The element itself has no ancient identity, having been isolated only in the nineteenth century, and its symbolic weight is now overwhelmingly modern, its name lending itself to Silicon Valley and the whole edifice of semiconductor electronics. Berzelius briefly favoured silicium, the metal-style spelling still used in several languages, before the metalloid ending silicon prevailed in English.

Flint's utility outlasted the Stone Age by millennia: struck against steel, it produced the sparks that fired flintlock muskets and pistols from the sixteenth century into the nineteenth, and flint and pyrite nodules served the same fire-starting purpose for hunter-gatherers many thousands of years earlier. The modern coinage Silicon Valley, applied to the district south of San Francisco, is usually credited to the journalist Don Hoefler, who used it in a 1971 trade-newspaper series describing the region's cluster of semiconductor firms, cementing silicon as the namesake of an entire industry and, eventually, of a whole model of technological economy.