Scientists Say: Silicon

Silicon is one of the most abundant — and useful — elements on Earth

The element silicon, naturally found in rocks such as the quartz pictured here, is used to make semiconductor components for modern electronics, including phones and computers.

Nicolò Grespi/EyeEm/Getty Images

By Maria Temming

January 10, 2022 at 6:30 am

Silicon (noun, “SILL-ih-ken”)

Silicon is a chemical element on the periodic table. It has an atomic number of 14, meaning it contains 14 protons. With properties between those of metals and non-metals, silicon is a “metalloid.” Its name comes from the Latin word “silex” or “silicis,” which means “flint.” Indeed, silicon is a key element in the rock flint.

Silicon is found in many rocks. It makes up more than 25 percent of Earth’s crust. In fact, it is the second most common element in the crust after oxygen. In nature, silicon is not usually found by itself. Instead, it is often paired with oxygen to form silica, or with oxygen and other elements to form silicates. Silica is found in sand, quartz and flint. Silicate minerals include granite, mica and feldspar.

Silicon is one of the most useful elements on Earth. For instance, it is a key ingredient of silicone. Silicone is a type of material used to make medical tools, cookware, adhesives and more. But silicon’s main claim to fame is modern electronics, such as phones and computers. In those devices, silicon acts as a semiconductor. That is a material that can transfer electricity at some times but not others. This allows silicon parts to act like tiny electrical on/off switches. Their “on” and “off” states encode the 1s and 0s of digital computer data. Without them, you would not be reading these words on a screen right now. That’s why the major hub of tech companies near San Francisco, Calif., is nicknamed “Silicon Valley.”