If you want to know where the data comes from for any particular property, then select that property. You'll see graphs for the properties as well.
Cerium is an iron-grey lustrous metal.
It is malleable, and oxidises very readily at room temperature, especially in moist air. Except for europium, cerium is the most reactive of the rare-earth metals. It slowly decomposes in cold water, and rapidly in hot water. Alkali solutions and dilute and concentrated acids attack the metal rapidly. The pure metal may ignite when scratched with a knife.