| It has six allotropes normally and a seventh under pressure, each of which have very similar energy levels but with significantly varying densities, making it very sensitive to changes in temperature, pressure, or chemistry, and allowing for dramatic volume changes following phase transitions. |
| The presence of these many allotropes makes machining plutonium very difficult, as it changes state very readily. |
| In weapons applications, plutonium is often alloyed with another metal (e.g.
gallium) to increase phase stability and thereby enhance workability and ease of handling. |
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See Also