Symbol:"Yb" Atomic Number:"70" Atomic Mass: 173.04amu. Ytterbium is one of the elements in the lanthanide series of inner transition elements. It may also be classified as a rare earth element. This silvery metal can be found in several minerals. It is never found as a pure element in nature, always in compounds.
More Information: Lanthanide Series
Symbol:"Y" Atomic Number:"39" Atomic Mass: 88.91amu. This is one of the transition elements found in period five of the periodic table. One of the rare Earth metals, yttrium is used in TV tubes, alloys, and has even been found on the Moon.
More Information: Transition Metals