About 200 years ago, scientists studying electricity realized that metals allowed electrical currents to flow through them much more easily than most nonmetals. Because of its relative abundance, high electrical conductivity, and malleability (or ability to be shaped), copper has become the standard material for electrical wiring and switching. Certain types of low-iron silicates, such as muscovite and pyrophyllite, are naturally occurring electrical insulators. Glass or porcelain insulators, made from such minerals as quartz and feldspar, keep high-voltage power-transmission lines from touching their poles. Pyrolusite is the naturally occurring mineral version of manganese oxide, which is inside every non-rechargeable alkaline battery. Gasoline-powered articles start their engines with a jolt of electricity from lead-acid batteries, which get their lead from the mineral galena. Other rechargeable batteries contain nickel, cadmium, or other metals, found in a variety of ores.

Certain rare elements such as beryllium, tantalum, lithium, and yttrium occur in small quantities scattered around the world, rather than in rich mineral veins that are easy to mine. The economic importance of these elements, however, has grown substantially over the past few decades, as scientists and engineers have found new ways to use them. For example, tantalum, found primarily in the mineral tantalite, helps miniaturize the electronic components inside computers, gaming consoles, and cell phones. Lithium powers those portable devices by making batteries last longer. Beryllium, found in more than 100 minerals, goes into lightweight structural components of fighter jets, guided missiles, and spacecraft. When added to diesel fuel, cerium lowers the noxious emissions from trucks. Gallium and indium, two elements that are considered electrical semiconductors, go into light-emitting diodes (LEDs). Yttrium is a key ingredient in medical lasers.

For example, the mineral bastnasite (or bastnaesite), which contains cerium, lanthanum, and yttrium, was discovered in Sweden and occurs. The economic importance of these elements, however, has grown substantially over the past few decades, as scientists have put them into many high-tech devices. Cerium added to diesel fuel helps trucks run with fewer noxious emissions; scandium, alloyed with aluminum and other metals, makes lightweight lacrosse sticks and components for fighter jets; yttrium is a key ingredient in medical lasers.