Gallium is a metal with a very low melting point. In fact it will melt in your hand after a few minutes. Once it is liquified, it is an interestingly dense liquid, similar to mercury (except gallium is non-toxic!) This vial contains 15g of this interesting element.
Non-toxic, but we wouldn't eat it. Like water, gallium expands when frozen, so don't store it in glass.
Gallium is a chemical element with the symbol Ga and atomic number 31. Elemental gallium is a soft, silvery metal at standard temperature and pressure; however in its liquid state it becomes silvery white. If too much force is applied, the gallium may fracture conchoidally. It is in group 13 of the periodic table, and thus has similarities to the other metals of the group, aluminium, indium, and thallium. Gallium does not occur as a free element in nature, but as gallium(III) compounds in trace amounts in zinc ores and in bauxite. Elemental gallium is a liquid at temperatures greater than 29.76 °C (85.57 °F), and will melt in a person's hands at normal human body temperature of 37 °C (99 °F).
The melting point of gallium is used as a temperature reference point. Gallium alloys are used in thermometers as a non-toxic and environmentally friendly alternative to mercury, and can withstand higher temperatures than mercury. An even lower melting point of −19 °C (−2 °F), well below the freezing point of water, is claimed for the alloy galinstan (62–95% gallium, 5–22% indium , and 0–16% tin by weight), but that may be the freezing point with the effect of supercooling.
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. Semiconducting 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 considered a technology-critical element.