Indium is a chemical element with the symbol In and atomic number 49. It is a post-transitional metal in Group 13 (triels) of the periodic table. Indium is a soft, silvery, malleable, and ductile metal. Indium is the rarest stable isotope in the periodic table, making up only 0.0001% of the Earth's crust. It is the 69th most abundant element in the universe. Indium is found in trace amounts in zinc, lead, and iron ores. It is also found in some meteorites. Indium is used in a variety of applications, including:

Soldering: Indium is used as a solder for metal surfaces because of its low melting point and good wetting properties.

Semiconductors: Indium is used in the production of semiconductors, such as gallium indium phosphide and indium gallium arsenide.

High-temperature alloys: Indium is used in the production of high-temperature alloys, such as those used in jet engines.

Flat-panel displays: Indium is used in the production of flat-panel displays, such as those used in televisions and computer monitors.

Touch screens: Indium is used in the production of touch screens for mobile devices and other electronic devices.

Indium is also used in the production of glass, ceramics, and batteries.