Why Is Thulium Expensive?

Like many lanthanides, pure thulium is made by treating its fluorine compound with calcium: Because it is so rare, thulium is also very expensive. It sells for about $50 a gram (about $23,000 a pound).

What's the cost of thulium?

Thulium metal costs $50/g. Thulium can be isolated by reduction of the oxide with lanthanum metal or by calcium reduction of a closed container. The element is silver-gray, soft, malleable, and ductile, and can be cut with a knife.

What makes thulium unique?

Thulium is a lanthanide element, it has a bright silvery-gray luster and can be cut by a knife. It is the least abundant of the rare earths and its metal is easy to work. It slowly tarnishes in air, but is more resistant to oxidation than most rare-earth elements.