|Origin of name:||From radium, as it was first detected as an emission from radium during radioactive decay|
|Atomic weight:||222 u|
|Melting point:||202 °K|
|Boiling point:||211.3 °K|
|Specific heat capacity:||0.094 J/(g*K)|
|Abundance in Earth's crust:||0.0000000000004 mg/kg|
|Natural occurrence:||form decay|
Data from Wikipedia's "List of chemical elements" (June 2017).
Not critical according to the European Commission (2014).