Column Descriptions

                                                                         
             Relative           Isotopic      Standard                   
Isotope      Atomic Mass        Composition   Atomic Weight    Notes     
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20  Ca  40   39.962590863(22)   0.96941(156)  40.078(4)        g
        42   41.95861783(16)    0.00647(23) 
        43   42.95876644(24)    0.00135(10) 
        44   43.95548156(35)    0.02086(110)
        46   45.9536890(24)     0.00004(3)  
        48   47.95252276(13)    0.00187(21) 
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