週期 6

55 Cs 銫 132.905 56 Ba 鋇 137.33 57 La 鑭 138.905 58 Ce 鈰 140.116 59 Pr 鐠 140.908 60 Nd 釹 144.24 61 Pm 鉕 144.913 62 Sm 釤 150.4 63 Eu 銪 151.964 64 Gd 釓 157.25 65 Tb 鋱 158.925 66 Dy 鏑 162.5 67 Ho 鈥 164.93 68 Er 鉺 167.26 69 Tm 銩 168.934 70 Yb 鐿 173.05 71 Lu 鎦 174.967 72 Hf 鉿 178.49 73 Ta 鉭 180.948 74 W 鎢 183.84 75 Re 錸 186.207 76 Os 鋨 190.2 77 Ir 銥 192.22 78 Pt 鉑 195.08 79 Au 金 196.967 80 Hg 汞 200.59 81 Tl 鉈 204.383 82 Pb 鉛 207 83 Bi 鉍 208.98 84 Po 釙 208.982 85 At 砈 209.987 86 Rn 氡 222.018