Yttrium (From Ytterby In Sweden Where The Minerals Containing It Were First Found), a rare metal, first obtained pure by Wöhler in 1828, the oxide of which, discovered by Gadolin in 1794, occurs in small quantity as a component of several minerals, such as gadolinite, yttrotantalite, yttro-titanite, yttro-cerite, etc. It is most conveniently obtained from its chloride by a method similar to that employed for aluminum. Its symbol is Y; atomic weight, 61.7. Metallic yttrium, as described by Berzelius, is a blackish gray powder, but this was undoubtedly a mixture of yttrium and erbium. In its impure state it is not oxidized in the air at red heat, nor by contact with steam; but in oxygen gas it burns brilliantly, yielding a white protoxide, or yttria. The oxide is best secured through a process employed to separate it from the mineral gadolinite; the carbonate is first formed, and being ignited, yttria remains. Yttria is a white powder, without odor or taste, soluble in the carbonates of the alkalies, especially that of ammonia; sp. gr. 4.842. When ignited it glows with a pure white light, and unlike erbia yields no bright bands in the spectrum. Upon precipitating its salts from an aqueous solution, it takes the form of a hydrate. With phosphorus, sulphur, iodine, etc, yttrium forms colorless and more or less crystalline salts.