Gallium is a chemical element with symbol Ga and atomic number 31. Elemental gallium does not occur in free form in nature, but as the gallium(III) compounds that are in trace amounts in zinc ores and in bauxite. Gallium is a soft, silvery metal, and elemental gallium is a brittle solid at low temperatures, and melts at 29.76 °C (85.57 °F) (slightly above room temperature). The melting point of gallium is used as a temperature reference point. The alloy galinstan (68.5% gallium, 21.5% indium, and 10% tin) has an even lower melting point of −19 °C (−2 °F), well below the freezing point of water. Since its discovery in 1875, gallium has been used as an agent to make alloys that melt at low temperatures. It has also been useful in semiconductors, including as a dopant.
Gallium is predominantly used in electronics. Gallium arsenide, the primary chemical compound of gallium in electronics, is used in microwave circuits, high-speed switching circuits, and infrared circuits. Semiconductive gallium nitride and indium gallium nitride produce blue and violet light-emitting diodes (LEDs) and diode lasers. Gallium is also used in the production of artificial gadolinium gallium garnet for jewelry.
Gallium is a chemical element.
Gallium may also refer to:
Galium is a large genus of annual and perennial herbaceous plants in the family Rubiaceae, occurring in the temperate zones of both the Northern and Southern Hemispheres. Some species are informally known as bedstraw.
There are over 600 species of Galium, with estimates of 629 to 650 as of 2013. The field madder, Sherardia arvensis, is a close relative and may be confused with a tiny bedstraw. Asperula is also a closely related genus; some species of Galium (such as woodruff, G. odoratum) are occasionally placed therein.