Carbon dating printing wood blocks
Likewise, different living things absorb or reject carbon-14 at different rates.
Two plants that died at the same moment, but which naturally contained different levels of radiocarbon, could be dated to drastically different times.
As samples get older, errors are magnified, and assumptions can render carbon dating all but useless.
For example, variations in greenhouse effects and solar radiation change how much carbon-14 a living organism is exposed to, which drastically changes the “starting point” from which a radiocarbon dating test is based.
Question: "Is carbon dating a reliable method for determining the age of things?
That’s not unusual in science, so far as it goes, but the relationship between assumptions and interpretations must be kept in mind. At worst, it can make carbon dating circular and self-confirming, though there are other means of dating that can reduce this risk.
Contamination and repeatability are also factors that have to be considered with carbon dating.
A tiny amount of carbon contamination will greatly skew test results, so sample preparation is critical.
For example, a steel spearhead cannot be carbon dated, so archaeologists might perform testing on the wooden shaft it was attached to.
This provides good information, but it only indicates how long ago that piece of wood was cut from a living tree.
The other major factor affecting the results of carbon dating is gauging the original proportion of carbon-14 itself.