Most carbon-14 quickly combines with oxygen to form radioactive carbon dioxide, which then spreads throughout the atmosphere.Plants take in carbon dioxide, incorporating in their tissues both carbon-14 (unstable) and normal carbon-12 (stable) in the same proportion as they occur in the atmosphere .The assumption usually made, but rarely acknowledged, is that the ratio of carbon-14 to carbon-12 in the atmosphere before the industrial revolution has always been the sameabout one in a trillion.Actually, that ratio may have been quite different.
However, before accepting any radiocarbon date, one should know how the technique works, its limitations, and its assumptions.
When creation scientists studied granite samples, they made interesting discoveries.
The samples were from a mile below the earth, which, according to inflated evolutionary years, were 1.5 billion years old.
In this interactive, learn how radiocarbon dating works, what it takes to determine a date in the lab, and why it's challenging to pinpoint a date precisely.
Outside the range of recorded history, calibration of the 14 clock is not possible.