what is ytterbium
References. Ytterbium (IPA : /ÉªËtÉË(r)biÉm/) is a chemical element in the periodic table that has the symbol Yb and atomic number 70. A soft silvery metallic element, ytterbium is a rare earth of the lanthanide series and is found in the minerals gadolinite, monazite, and xenotime. The element is sometimes associated with yttrium or other related elements and is used in certain steels.