Pure thulium is never found in nature, but it is found in small amounts in minerals along with other rare earths. It is mostly taken from monazite found in ores in China, Brazil, India, Sri Lanki, the United States and Australia.
Thulium is silvery-grey and can be cut by a knife. It is a lenthanide element and is the least abundant of the rare earths. It is the second-rarest lenthanide element. Thulium is resistant to corrosion, and it is a good conductor of electricity. Because the element is so rare and expensive, it has few commercial uses outside of chemical research.