Atomic Weights and Isotopic Compositions for Radium
Column Descriptions

                                                                         
             Relative           Isotopic      Standard                   
Isotope      Atomic Mass        Composition   Atomic Weight    Notes     
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88  Ra  223  223.0185023(27)                  [226]             
        224  224.0202120(23)                
        226  226.0254103(25)                
        228  228.0310707(26)                
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