Definition of "cerium" []

• A lustrous, iron-gray, malleable metallic rare-earth element that occurs chiefly in the minerals monazite and bastnaesite, exists in four allotropic states, is a constituent of lighter flint alloys, and is used in various metallurgical and nuclear applications. Atomic number 58; atomic weight 140.12; melting point 795°C; boiling point 3,468°C; specific gravity 6.67 to 8.23; valence 3, 4. See Table at element. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "That set off a surge in prices for rare-earth minerals such as lanthanum, often used to make catalysts for refineries, and cerium, which is sometimes used in glass."
• "Calcium and a rare earth element called cerium hint at the extent of the world's deserts, while sodium is a measure of ocean storminess and sea spray."
• "It mined europium, which forms the basis of the high-efficiency lighting industry; lanthanum, without which it would be difficult to refine gas; and cerium, which is used to polish the glass on computer screens and cellphones."