Thulium is a rare earth metal that is silvery-gray in color and is relatively soft and malleable. It is typically found in small amounts in various minerals, including monazite and xenotime. Thulium has unique properties that make it useful in a wide range of industries. For example, its ability to absorb and emit radiation makes it valuable for use in portable X-ray machines and other medical applications. Thulium is also used as a dopant in fiber optic amplifiers, which are critical components in telecommunications infrastructure. In addition, thulium is used in high-temperature superconductors, which have a range of applications in electrical engineering, and as a catalyst in certain chemical reactions. However, thulium is relatively expensive and difficult to obtain, making it less common in industrial applications than other lanthanide metals.