What is meant by the ‘calibration’ of radiocarbon dates, how is it achieved and why is it important?
I suggest that if you read the previous answer then you do so very carefully. It stems from the Creationist lobby and is highly biased and misrepresentative. (For example it uses the argument that because coal has C14 in it then it can’t be as old as it is commonly said to be. This is a non-argument (like so much else in creationist-land) as the C14 could have easily been created by radioactive emissions from nearby rock deposits.) Earths atmosphere contains a small percentage of Carbon-14, and this is absorbed by all living things during their life. When they die this absorption tends to stop. Radiocarbon dating works by measuring the proportion of Carbon-14 in a sample. Carbon-14 decays radioactively with a half life of about 6,000 years (I can’t remember exactly) – so gradually, over time, the proportion of C14 will reduce. If we know how much was in the atmosphere to start with then we can calculate the age of the sample. However, that “if” can lead to inaccuracy. Many processes ha
