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Terbium is a chemical element with symbol Tb and atomic number 65. It is a silvery-white rare earth metal that is malleable, ductile and soft enough to be cut with a knife.
T 0149 (OTTO) Terbium pieces, 99.9% Cas 7440-27-9 - used in solid-state devices, and as a crystal stabilizer of fuel cells which operate at elevated temperatures.