Column Descriptions

                                                                         
             Relative           Isotopic      Standard                   
Isotope      Atomic Mass        Composition   Atomic Weight    Notes     
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26  Fe  54   53.93960899(53)    0.05845(35)   55.845(2)         
        56   55.93493633(49)    0.91754(36) 
        57   56.93539284(49)    0.02119(10) 
        58   57.93327443(53)    0.00282(4)  
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