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Thulium is a Chemical element that has the symbol Tm and Atomic number 69 in the Periodic table. A "Lanthanide" element, thulium is the least abundant of the Rare earth and its Metal is easy to work, has a bright silvery-gray luster and can be cut by a knife. It also has some Corrosion resistance in dry air and good Ductility. Naturally occurring thulium is made entirely of the Stable isotope Tm-169.
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