Those that have a vested interest in Carbon Dating of ancient artifacts try to give the impression that their results are scientifically indisputable.
This impression is not really true.The dating technique is based on a whole set of assumptions, which if one of those assumptions is false or flawed, the results will yield dates that differ radically from the true dates of the objects tested.
Fish corrupt Carbon-14 dating
Danish Stone Age settlements may have been misdated by up to 2,000 years. In sites where people ate fish, there might well be errors in the Carbon-14 dating of clay vessels.
Fish contain less Carbon-14
This is due to the fact that fish contain less of the radioactive substance Carbon 14 if they have lived in hard water.
Hard water contains high levels of calcium carbonate. Carbonate contains carbon, including carbon-14. However, depending on ocean water circulation, fish and other living creatures can incorporate ‘older’ carbonate (with less carbon-14) into their bodies. When these organisms die and fossilize, they appear to be much older than they actually are.
An experiment made things clearer:
The archaeologists created a clay vessel of the kind that was used in the Stone Age.
They placed it over a fire and prepared a fish dish in it.
They made sure that some of it stuck to the pot.
They then Carbon-14 dated the pot and the burnt crust at the bottom of the pot. The dating showed that the pot and the burnt fish, Carbon-14-wise, were 700 years old.