Interesting fact about americium

Americium is highly radioactive. Freshly prepared americium metal gives off a white, somewhat silvery luster. It tarnishes slowly in dry air at room temperature. Americium is more malleable than uranium or neptunium. Americium has numerous compounds. In solutions, americium has oxidation states III, IV, V, and VI. In carbonate solutions, americium can coexist in all four oxidation states simultaneously. It is only the second element, after plutonium, to do this.