Scandium
Background Scandium was discovered by Nilson in 1876. It was found in the minerals euxenite and gadolinite, which at the time were unique to Scandinavia. The material that Nilson had identified was identical to ekaboron, a material that Mendeleev had predicted would exist many years before.
Scandium metal was not prepared until 1937. At this time Fisher, Brunger and Grieneisen were able to isolate it from a eutectic mixture of scandium, potassium and lithium chlorides.
AbundanceScandium is more abundant in the sun than it is on Earth. In the sun it is the 23rd most common element, whilst on earth it ranks only 50th. Similarly, it is more abundant on some stars than Earth.
OccurrenceScandium can be found in tiny amounts in about 800 different minerals.
It is the main constituent of the rare mineral thortveitite from Scandinavia and Malagasy. Thortveitite is the main source of Scandium and is most often produced as a by-product or uranium mill tailings.
Other sources of scandium are:
· Residues from tungsten extraction Zinnwald wolframite
· Wiikite
· Bazzite
ProductionScandium metal is produced by the reduction of scandium fluoride with calcium metal. Key Properties · Scandium is bluish-white in colour, but may develop a yellowish to pinkish hue upon exposure to air
· It is relatively soft
· It is very light
· It has a higher melting point than aluminium
· Although scandium reacts readily with many acids it does not react with a 1:1 mixture of concentrated nitric acid and 48% hydrofluoric acid Applications · The radioactive isotope Sc46 is used in crude oil refinery crackers as a tracing agent
· Scandium oxide is used in high intensity lights
· Scandium iodide is added to mercury vapour lamps for high efficiency lights used in night time colour television transmission.
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