A wide range of nuclear techniques are used by archaeologists to determine the age of items. Artefacts such as the Shroud of Turin, the Dead Sea Scrolls and Charlemagne’s Crown can be dated, and their authenticity verified, using nuclear techniques.
ANSTO has been involved in dating the Kelly Gang's armour and key periods in the history of the urban complex at Angkor in Cambodia, once the capital of a vast medieval empire that incorporated most of mainland Southeast Asia during 12/13th Centuries. A team examined land use change to gain a better understanding of the cause of Angkor's decline.
Nuclear techniques can also be used to determine the origins of an item and even the production process used. Human skeletal and other remains can be analysed in order to answer questions about the life and diet of ancient people. Trace elements can be altered by conditions in the burial environment, so various techniques are used to analyse the soil from the burial environment.
Radiocarbon dating uses the naturally occurring radioisotope carbon-14 to determine the age of organic materials. Plants take up atmospheric carbon dioxide by photosynthesis, and are ingested by animals. When an organism dies, however, its ratio of carbon-14 to carbon-12 begins to gradually decrease through radioactive decay.
When dating a sample, scientists use this ratio to calculate the age of the sample.
At ANSTO radiocarbon dating utilises the ANTARES accelerator, which requires very small samples compared to standard radiocarbon dating, and can date samples much more precisely.
Potassium argon dating is another technique used to date very old archaeological materials and has been used to date rocks as old as four billion years.