Holmium

Elemental holmium is a relatively soft and malleable, silvery-white metal. Holmium is found in the minerals monazite and gadolinite. Trivalent holmium ions have fluorescent properties similar to many other rare-earth ions (while yielding their own set of unique emission light lines), and thus are used in the same way as some other rare earths in certain laser and glass-colorant applications. Holmium has the highest magnetic permeability of any element and therefore is used for the polepieces of the strongest static magnets