Citrine, Walter McLennan Citrine, 1st Baron, 1887-1983, English trade union leader. An electrician, he became district secretary of the electrical trade union in 1914 and rose to be general secretary of the Trades Union Congress in 1926, president of the International Federation of Trades Unions in 1928, and president of the World Trade Union Conference in 1945. A skillful organizer, he led the conservative wing in labor and became powerful in the Labour government of Clement Attlee. He was created baron in 1946 and was chairman of the Central Electricity Authority (1947-57). His writings include My Finnish Diary (1940), In Russia Now (1942), and British Trade Unions (1942).

Transparent, coarse-grained variety of the silica mineral quartz. Citrine is a semiprecious gem that is valued for its yellow to brownish colour and its resemblance to the rarer topaz. Natural citrine is rarer than amethyst or smoky quartz, both of which are often heated to change their natural colour to that of citrine. Citrine is often marketed under various names that confuse it with topaz to inflate its price; it may be distinguished from topaz by its inferior hardness. It occurs mainly in Brazil, Uruguay, the Ural Mountains, Scotland, and North Carolina.

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