Column Descriptions

                                                                         
             Relative           Isotopic      Standard                   
Isotope      Atomic Mass        Composition   Atomic Weight    Notes     
_________________________________________________________________________
12  Mg  24   23.985041697(14)   0.7899(4)     [24.304,24.307]   
        25   24.985836976(50)   0.1000(1)   
        26   25.982592968(31)   0.1101(3)   
_________________________________________________________________________

NIST | Physical Measurement Laboratory | Physical Reference Data | Atomic Weights and Isotopic Compositions Main Page