鉲是人造元素，沒有穩定同位素。它有 20 種同位素，原子量介於 237 至 256 之間，其中半衰期 898 年的 251Cf 最穩定。 圖表 rowspan3237Cf rowspan3 styletextalignright 98 rowspan3 styletextalignright 139 rowspan323706207 54 rowspan321 3 s SF various rowspan352 237Bk 233Cm rowspan3238Cf rowspan3 styletextalignright 98 rowspan3 styletextalignright 140 rowspan323806141 43 rowspan3211 13 ms SF various rowspan30 （不常見） 238Bk （不常見） 234Cm rowspan2239Cf rowspan2 styletextalignright 98 rowspan2 styletextalignright 141 rowspan223906242 23 rowspan260 30 s 39 3712 s 235Cm rowspan252 （不常見） 239Bk rowspan3240Cf rowspan3 styletextalignright 98 rowspan3 styletextalignright 142 rowspan324006230 22 rowspan3106 15 min 98 236Cm rowspan30 SF 2 various （不常見） 240Bk rowspan2241Cf rowspan2 styletextalignright 98 rowspan2 styletextalignright 143 rowspan224106373 27 rowspan2378 70 min 75 241Bk rowspan272 25 237Cm rowspan3242Cf rowspan3 styletextalignright 98 rowspan3 styletextalignright 144 rowspan324206370 4 rowspan3349 15 min 80 238Cm rowspan30 20 242Bk SF 014 various rowspan2243Cf rowspan2 styletextalignright 98 rowspan2 styletextalignright 145 rowspan224306543 15 rowspan2107 5 min 86 243Bk rowspan212 14 239Cm rowspan2244Cf rowspan2 styletextalignright 98 rowspan2 styletextalignright 146 rowspan2244066001 3 rowspan2194 6 min 99 240Cm rowspan20 1 244Bk rowspan2245Cf rowspan2 styletextalignright 98 rowspan2 styletextalignright 147 rowspan2245068049 3 rowspan2450 15 min 64 245Bk rowspan252 36 241Cm rowspan3246Cf rowspan3 styletextalignright 98 rowspan3 styletextalignright 148 rowspan32460688053 22 rowspan3357 5 h 242Cm rowspan30 5104 246Bk SF 2104 various rowspan2247Cf rowspan2 styletextalignright 98 rowspan2 styletextalignright 149 rowspan2247071001 9 rowspan2311 3 h 9996 247Bk rowspan272 04 243Cm rowspan2248Cf rowspan2 styletextalignright 98 rowspan2 styletextalignright 150 rowspan2248072185 6 rowspan23335 28 d 9999 244Cm rowspan20 SF 0029 various rowspan2249Cf rowspan2 styletextalignright 98 rowspan2 styletextalignright 151 rowspan22490748535 24 rowspan2351 2 y 245Cm rowspan292 SF 5107 various styletextindent1em 249mCf colspan3 styletextindent2em 14498 5 keV 45 5 µs 52 rowspan2250Cf rowspan2 styletextalignright 98 rowspan2 styletextalignright 152 rowspan22500764061 22 rowspan21308 9 y 9992 246Cm rowspan20 SF 077 various 251CfHigh neutron crosssection tends to absorb neutrons styletextalignright 98 styletextalignright 153 251079587 5 900 40 y 247Cm 12 rowspan2252CfMost common isotope rowspan2 styletextalignright 98 rowspan2 styletextalignright 154 rowspan2252081626 5 rowspan22645 8 y 969 248Cm rowspan20 SF 309 High neutron emitter average 37 neutrons per fission various rowspan2253Cf rowspan2 styletextalignright 98 rowspan2 styletextalignright 155 rowspan2253085133 7 rowspan21781 8 d 9969 253Es rowspan272 31 249Cm rowspan2 254Cf rowspan2 styletextalignright 98 rowspan2 styletextalignright 156 rowspan2 254087323 13 rowspan2 605 2 d SF 9969 various rowspan2 0 31 250Cm rowspan3255Cf rowspan3 styletextalignright 98 rowspan3 styletextalignright 157 rowspan325509105 22 rowspan385 18 min 9999 255Es rowspan372 SF 001 various 105 251Cm rowspan3 256Cf rowspan3 styletextalignright 98 rowspan3 styletextalignright 158 rowspan3 25609344 32 rowspan3 123 12 min SF 99 various rowspan3 0 1 256Es 參考文獻 Isotope masses from Ame2003 Atomic Mass Evaluation by G Audi AH Wapstra C Thibault J Blachot and O Bersillon in Nuclear Physics A729 2003 Halflife spin and isomer data selected from these sources Editing notes on this articles talk page Audi Bersillon Blachot Wapstra The Nubase2003 evaluation of nuclear and decay properties Nuc Phys A 729 pp 3128 2003 National Nuclear Data Center Brookhaven National Laboratory Information extracted from the NuDat 21 database retrieved Sept 2005 David R Lide ed Norman E Holden in CRC Handbook of Chemistry and Physics 85th Edition online version CRC Press Boca Raton Florida 2005 Section 11 Table of the Isotopes Cf Category 鉲 heקליפורניוםאיזוטופים של קליפורניום