Ytterbium free from rare earths has very limited commercial applications. The element is used in lasers (102 nm) and as a doping agent. The radioisotope has been used in portable industrial units to examine thin layers of steel and aluminum sections and also in x-ray units for medical purposes. One of the most important uses of the element is in pure and applied experimental research. Ytterbium is mainly used in rare earths salt and metal mixtures. Mixtures of oxides containing ytterbium, are used in carbon bars for industrial lighting, in dielectrics and titanium capacitors and still as catalysts and addictive in glass production. The mixture of rare earth metals is used to control the grain size and to improve hardness and other mechanical properties of inox materials and non ferrous alloys.