Ytterbium is a member of the lanthanides and one of the earth's rare metals. Its chemical symbol Yb and its atomic number is 70. Ytterbium melts at 1092 K (819C or 1506F) and its boiling point is 1469 K (1196C or 2185F). It is a solid at room temperature and its density is 6.90 grams per cubic centimeter.
Ytterbium was discovered in the mineral gadolinite in a quarry near a Swedish town named, Ytterby, hence the name of this element. Many lanthanides are sources in this area. In 1843, a Swedish chemist, Carl Gustaf Mosander, separated the gadolinite into three materials, which he named yttria, erbia and terbia. Erbia and terbia were later confused and their names reversed. Later, in 1878, a Swiss chemist named Jean Charles Galissard de Marignac discovered that erbia was made of two different components. He named one ytterbia and the other retained the name erbia. It was Marignac who decided that ytterbia was a compound of a new element, so he named it ytterbium. Other scientists differed in their results of experiments on this mineral, until the French chemist George Urbain was able to separate ytterbium into two elements. Urbain named one neoytterbium (new ytterbium) and the other lutecium. Eventually neoytterbium became ytterbium and they changed the spelling of lutecium to lutetium. However, Marignac is still credited with the discovery of ytterbium.
The lanthanides are soft silvery metals, whose name means "hidden". They are very much alike and hard to distinguish from each other. They are members of the rare earth metal group, but many of them are not rare at all. Cerium is more common on earth than Copper. The least common lanthanide is Thulium and it is more common than silver. The lanthanides were discovered in the first half of the Twentieth Century.
The lanthanides have strong refractory effects and are thus used in light equipment and in lenses. They are also useful in lasers, CDs, and as colorants. Their emissions make the color in color television. They also have strong magnetic qualities and can run miniature motors. In this usage the lanthanides have become very common in technology. You also find lanthanides in electron microscopes and superconductors. Samarium is used to make the carbon lights that are in use in the motion picture industry, and are therefore responsible for the movies we see. They also make up the flint for cigarette lighters.
Ytterbium is primarily obtained through an ion exchange process from monazite sand. It has few uses, mainly added to stainless steel to make it stronger or to amplify fiber optic cable's ability to amplify sound. One if its isotopes is under exploration as a possible source of radiation for mobile X-ray units.