I have compiled a list of sources for the elements that are available to the amateur chemist. Thulium, ytterbium, and
lutetium will be discussed here.
Thulium is a typical rare earth metal. Its compounds are pale green to yellow. No sources of it are available to the general public.
Ytterbium is another rare earth metal. Its liquid range from 824-1196 C is the smallest of all metals. Most ytterbium compounds are white and boring. It does form divalent compounds, however, of which the chloride is green. Earthquake meters may contain ytterbium metal to measure the quake, but it is unlikely that they do.
Lutetium is the last of the rare earth metals. It is the rarest and most expensive one. Its compounds are boring and white. Lutetium tantalate is the densest white substance besides thorium dioxide, which is slightly radioactive. There are no household sources.
Here ends the sequence of little articles about rare earth metals.