Historical artefacts like moa bones can be dated using a technique that measures the activity of the radioisotope carbon-14 still present in the sample.
By comparing this with a modern standard, an estimate of the calendar age of the artefact can be made.
This allows corrections to be made on radiocarbon dates in order to produce more accurate dates.
Radiocarbon dating, or carbon-14 dating, can be used to date material that had its origins in a living thing as long as the material contains carbon.
Fiona is wearing an aspirator because of the carcinogenic properties of benzene.
Special silica glass vials are used to contain the mixture of benzene and PBD.
The scintillator chemical butyl-PBD picks up each decay event and emits a tiny flash of light that the spectrometer is programmed to detect and count.
In addition to the moa sample, control samples are also measured at the same time.The silica glass vials are loaded into the liquid scintillation spectrometer.The C-14 atoms present in the benzene decay at a certain rate.To obtain a calendar age for the sample, this radiocarbon age needs to be compared against samples of known age by means of a calibration curve using a specially designed computer software application.This application uses a terrestrial calibration curve to calculate the calendar age.All air is evacuated from the vacuum line because it has C-14 in it and is a potential contaminant.