Cerithium (serithium)

[NL., also Ce ritium; a modification of Gr. κεράτιον, a little horn, dim. of κέρας, a horn.] The typical genus of club shells of the family Cerithiidæ. The species are numerous. C. obtusum is an example. cerium (sē'ri-um), n. [NL., named by Berzelius in 1803 from the planet Ceres.] Chemical symbol, Ce; atomic weight, 141.5; specific gravity, 5.5. A metal discovered in 1803 by Klaproth, Hi singer, and Berzelius independently. It is a powder of lamellar texture, malleable, of a color between that of iron and that of lead, and acquires a metallic luster by pre ure. It becomes bright by polishing, but soon tarnishes in the air. It does not occur native, but Club-shell ( Cerithium obtusum ). exists in combination in the mineral cerite, in which it was first found, as also in allanite, gadolinite, and some others.