Noun
The oxide, Y2O3, or earth, of yttrium.
Source: Webster's dictionaryIt is now thought that workers using double sodium or potassium sulfates to remove ceria from yttria inadvertently lost the terbium into the ceria-containing precipitate. Source: Internet
This divide is reflected in the first two "rare earths" that were discovered: yttria (1794) and ceria (1803). Source: Internet
What is now known as terbium was only about 1% of the original yttria, but that was sufficient to impart a yellowish color to the yttrium oxide. Source: Internet