Gallium
Today, almost all gallium is used for microelectronics. Gallium arsenide, the primary use of gallium, is used in microwave circuitry and infrared applications. Gallium nitride and indium gallium nitride, minority semiconductor uses, produce blue and violet light-emitting diodes (LEDs) and diode lasers.
Elemental gallium is not found in nature, but it is easily obtained by smelting. Very pure gallium metal has a brilliant silvery color and its solid metal fractures like glass. Gallium metal expands by 3.1% when it solidifies, and therefore storage in either glass or metal containers is avoided, due to the possibility of container rupture with freezing. Gallium shares the higher-density liquid state with only a few materials like silicon, germanium, bismuth and water.