Atomic Weights and Isotopic Compositions for Thorium
Column Descriptions

                                                                         
             Relative           Isotopic      Standard                   
Isotope      Atomic Mass        Composition   Atomic Weight    Notes     
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90  Th  230  230.0331341(19)                  232.0377(4)      g
        232  232.0380558(21)    1           
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