Calibrated vs uncalibrated carbon dating
In this way large domed tombs (known as tholos or beehive tombs) in Greece were thought to predate similar structures in the Scottish Island of Maeshowe.This supported the idea that the classical worlds of Greece and Rome were at the centre of all innovations.Luckily, we can measure these fluctuations in samples that are dated by other methods.Tree rings can be counted and their radiocarbon content measured.The calibrated date is also presented, either in BC or AD or with the unit cal BP (calibrated before present - before 1950).
In the early years of radiocarbon dating a product’s decay was measured, but this required huge samples (e.g. Many labs now use an Accelerator Mass Spectrometer (AMS), a machine that can detect and measure the presence of different isotopes, to count the individual C atoms in a sample.
In addition, samples need to be thoroughly cleaned to remove carbon contamination from glues and soil before dating.
This is particularly important for very old samples.
Rachel Wood does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
Radiocarbon dating has transformed our understanding of the past 50,000 years.