How is Carbon Dating done? How can I do it? How can I become an archaeologist? What education and qualifications are required for it? Rijul Jain

Hi Rijul, thank you for your questions!

Let’s see, we’re going to have to get a little scientific…

Carbon dating or radiocarbon dating is a scientific method for dating organic material. Organic material consists of plant or animal remains. It is done by looking at the make up and amount of the element Carbon within a sample of organic material.

Carbon has two stable isotopes, 12C and 11C, and one unstable isotope, 14C. Isotopes are atoms of an element with the normal number of proton and electron particles for that element, but with different numbers of neutrons; so Carbon 12 (12C) has 12 neutrons, Carbon 11 (11C) has 11, and Carbon 14 (14C) has 14 neutrons. With me so far?

During the lifetime of a plant or animal it exchanges carbon with its surroundings. For example, we breathe in oxygen and breathe out carbon dioxide, whereas most plants ‘breathe’ in carbon dioxide and ‘breathe’ out oxygen when they respire. When a plant or animal dies it is assumed that level of 12C and 14C within the organism is in a specific ratio to the level of 12C and 14C in the atmosphere. However, at the point of death, the organism stops absorbing carbon and so this ratio will change.

Now, the good thing about the unstable isotope 14C is that it is unstable! That means it decays or breaks down, and, we know just how fast it breaks down. We know that 14C has a half-life of 5,730 years; so this means that after 5,730 years the remains of the organism will only contain half the 14C it did when it died. It then follows that a quarter of the original 14C will remain after 11,460, an eighth after 17,190 years and so on.

So, when we test a sample, we measure the number of 12C atoms present and this tells us how much 14C was there originally was. We then measure how much 14C the sample contains and this tells us how much of the unstable isotope 14C has decayed. And as we know the rate of decay we can date the sample! Ta-da! Ain’t Science Brilliant?

As to how you can do it, I think you’re going have to well in school, particularly in Chemistry, perhaps do a Science degree at university and then look for a job in a testing lab!

If you want to become an archaeologist, again I would suggest doing well in school up to A-Level standard, particularly in the Sciences, History and English. Now it’s possible that at this point you could become a trainee/apprentice archaeologist. Some of the bigger archaeological employers offer these positions. Or perhaps you could go to university and take a degree course in Archaeology; it’s up to you really!

All the best and work hard Rijul!

Phil