galinstan, a liquid alloy of gallium, indium, and tin, as a replacement for mercury

As of 2012, many mercury-in-glass thermometers are used in meteorology; however, they are becoming increasingly rare for other uses, as many countries banned them formedical use due to the toxicity of mercury. Some manufacturers use galinstan, a liquid alloy of gallium, indium, and tin, as a replacement for mercury.

https://en.wikipedia.org/wiki/Mercury-in-glass_thermometer