Uranium Hexafluoride (UF6)

Uranium Hexaflouride

"Uranium hexafluoride is a chemical compound consisting of one atom of uranium combined with six atoms of fluorine. It is the chemical form of uranium that is used during the uranium enrichment process. Within a reasonable range of temperature and pressure, it can be a solid, liquid, or gas. Solid UF6 is a white, dense, crystalline material that resembles rock salt."

https://web.evs.anl.gov/uranium/guide/uf6/index.cfm#:~:text=Uranium%20hexafluoride%20is%20a%20chemical,solid%2C%20liquid%2C%20or%20gas.