Some of the materials used to construct smartphones are household names like “silicon,” which is used for circuit boards, or “graphite” used in batteries. Then there are lesser known substances like bastnaesite, monazite, and xenotime. These brownish minerals contain neodymium, one of the rare-earth elements used in the magnets that allow smartphone speakers to play music and the vibration motor that notifies you of new, funny cat videos on social media.
Other minerals used for smartphones include bauxite, the primary source of gallium used for light emitting diode screen backlighting and amplifiers; sphalerite, which is the source of indium used in the screen’s conductive coating; and arsenopyrite, a source of arsenic, which is used in radio frequency and power amplifiers in the form of gallium arsenide. Even an element as common as copper, which conducts electricity and heat, comes from minerals like chalcopyrite and bornite.
Ordinary Minerals Give Smartphones Extraordinary Capabilities, from the USGS.