Gadolinium is a chemical element with the symbol Gd and atomic number 64. It is a silvery-white metal that belongs to the lanthanide series of the periodic table. Gadolinium is known for its high magnetic susceptibility, making it useful in various applications, including magnetic resonance imaging (MRI) as a contrast agent. In nature, gadolinium is found in minerals such as monazite and bastnäsite. It is primarily used in electronics, nuclear reactors, and in the production of strong permanent magnets. Gadolinium compounds are also employed in the manufacturing of phosphors for color television tubes and LED lights.