Radiocarbon dating can’t tell the difference between wood that was cut and immediately used for the spear, and wood that was cut years before being re-used for that purpose.Nor can it tell if a much older spearhead was attached to a brand-new shaft.As samples get older, errors are magnified, and assumptions can render carbon dating all but useless.
This makes the results subject to the researchers’ assumptions about those objects.
Second, radiocarbon dating becomes more difficult, and less accurate, as the sample gets older.
The bodies of living things generally have concentrations of the isotope carbon-14, also known as radiocarbon, identical to concentrations in the atmosphere.
In short, carbon dating is as useful as any other technique, so long as it’s done properly and the results are objectively interpreted.
It is not, however, an inherently error-free or black-and-white method for dating objects.