Abstract
Radiocarbon dating of ancient organic material is based on the radioactive decay of 14C, with a half-life of 5730 years, or with a decay constant ln2/(5730 years) = 0.121 per millennium. After 100 millennia, the 14C has decayed to an undetectably minute fraction of its original value (less than 6 millionths). However, in rocks or minerals millions of years old, contamination by modern carbon or other processes may introduce tiny amounts of 14C. To interpret these as due to decay of original organic 14C, and thus to get an apparent age, is quite mistaken.