Atomic Weights and Isotopic Compositions for Iron
 Isotope   Relative
Atomic Mass 		    Isotopic
  Composition  		 Standard
Atomic Weight 		  Notes 
 
26 Fe 54   53.939 608 99(53)   0.058 45(35)    55.845(2)  
56   55.934 936 33(49)   0.917 54(36)
57   56.935 392 84(49)   0.021 19(10)
58   57.933 274 43(53)   0.002 82(4)

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