Scandium is a rare earth metal element denoted by the atomic symbol Sc. Its atomic weight is 44.9559; its atomic number is 21; and it melts at 2805.8°F (1541°C). Scandium is a silvery-white metal which develops a yellowish or pinkish cast when exposed to air.
In 1876, the Swedish chemist Lars Nilson (1840-1899) discovered the element while analyzing a complex mineral known as euxenite. Nilson named the element in honor of Scandinavia, his homeland, and the only place in the world that euxenite had yet been found. Nilson also obtained scandium from gadolinite, another mineral found only in Scandinavia.
The significance of Nilson's discovery was pointed out by his countryman, Per Teodor Cleve (1840-1905). Cleve showed that scandium's chemical and physical properties closely matched those of the "eka-boron" that had been predicted for element 21 by Dmitri Mendeleev a decade earlier. The close match of properties for eka-boron and scandium added further confirmation of Mendeleev's periodic law.
Scandium is typically obtained by extraction from the mineral thortveitite or from uranium mill tailing. The scandium is further purified by reducing the scandium fluoride with calcium. In the United States, about 20 kg of scandium is used annually in the production of high-intensity lamps. Since it is very lightweight, scandium has been used as an alloy for high-performance bicycle frames.