Indium

Indium is a chemical element with the symbol In and atomic number 49. It is a delicate white-silver chemical element. Indium has a melting point slightly higher than sodium and gallium, but slightly lower than lithium and tin. Depending on purity and quantity, indium costs between $1 and $5 per gram.

Ferdinand Reich and Hieronymous Theodor Ritcher used spectroscopic methods to detect it in 1863. It was given the name Indium because of the indigo blue line in its spectrum. Indium is most widely utilized in the semiconductor sector for alloys, soldiers, and high-vacuum soft-metal seals.

Indium is the softest metal on the planet, except for Alkali, and is a post-transition metal that makes up about 0.21 parts per million of the earth's crust.

Price: $1-$5 per gram