Column Descriptions

                                                                         
             Relative           Isotopic      Standard                   
Isotope      Atomic Mass        Composition   Atomic Weight    Notes     
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37  Rb  85   84.9117897379(54)  0.7217(2)     85.4678(3)       g
        87   86.9091805310(60)  0.2783(2)   
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