Plutonium

• Plutonium is a heavy gray, metal
• It look rather like nickel when freshly machined.
• In air it discolors and soon begins to look like tarnished silver; it turns black. The rate of tarnishing depends on the particular alloy of plutonium and atmospheric humidity, but might typically occur within a day. in a few days then corrosion layer thickness, turns olive-colored, and flakes off as plutonium oxide
• plutonium metal in pieces like the one shown here is not pyrophoric .it does not burn spontaneously in air
• Its density 19.86 g/cm3, a little greater than gold.