Column Descriptions

                                                                         
             Relative           Isotopic      Standard                   
Isotope      Atomic Mass        Composition   Atomic Weight    Notes     
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81  Tl  203  202.9723446(14)    0.2952(1)     [204.382,204.385]   
        205  204.9744278(14)    0.7048(1)   
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