The few high-gallium minerals such as Gallite (CuGaS2) are too rare to serve as a primary source of the element or its compounds.
Gallium is found and extracted as a trace component in Bauxite and to a small extent from Sphalerite.
The amount extracted from Coal, Diaspore, and Germanite in which Gallium is also present is negligible.
The melting point of Gallium is used as a Temperature Reference Point, & its alloy Galinstan.
Gallium has been used as an agent to make alloys that melt at low temperature. It has also been used in semiconductors, including as dopant.
Gallium is predominantly used in electronics.
Gallium metal expands by 3.1% when it solidifies.
Gallium shares the higher-density liquid state with only a few materials, like water, Silicon, Germanium, Bismuth, & Plutonium.
Gallium is one of the metals, with Caesium, Rubidium, Mercury, and likely Francium, that are liquid at or near-normal room temperature, used as High-Temperature Thermometers.
It has greatest ratio between melting and boiling point.