Carbon dating technique
Until this century, relative dating was the only technique for identifying the age of a truly ancient object.By examining the object's relation to layers of deposits in the area, and by comparing the object to others found at the site, archaeologists can estimate when the object arrived at the site.
University of Leicester archaeologists took four small samples from one of the ribs of the Greyfriars skeleton and sent them to two specialist units with the facilities to analyse them: the Scottish Universities Environmental Research Centre (SUERC) at the University of Glasgow, and the Oxford Radiocarbon Accelerator Unit, part of the University of Oxford’s Research Laboratory for Archaeology and the History of Art.A commonly used radiometric dating technique relies on the breakdown of potassium (Ar in an igneous rock can tell us the amount of time that has passed since the rock crystallized.If an igneous or other rock is metamorphosed, its radiometric clock is reset, and potassium-argon measurements can be used to tell the number of years that has passed since metamorphism.Radioactive elements are unstable; they breakdown spontaneously into more stable atoms over time, a process known as radioactive decay.Radioactive decay occurs at a constant rate, specific to each radioactive isotope.Radioactive elements were incorporated into the Earth when the Solar System formed.
All rocks and minerals contain tiny amounts of these radioactive elements.
Carbon-14 is a method used for young (less than 50,000 year old) sedimentary rocks.
This method relies on the uptake of a naturally occurring radioactive isotope of carbon, carbon-14 by all living things.
Though still heavily used, relative dating is now augmented by several modern dating techniques.
Radiocarbon dating involves determining the age of an ancient fossil or specimen by measuring its carbon-14 content.
How old are the bones found under the Greyfriars church?