Radiocarbon dates are presented in two ways because of this complication.
The uncalibrated date is given with the unit BP (radiocarbon years before 1950).
In 2008 we could only calibrate radiocarbon dates until 26,000 years.
Now the curve extends (tentatively) to 50,000 years.
Some of the first radiocarbon dates produced showed that the Scottish tombs were thousands of years older than those in Greece.
The barbarians of the north were capable of designing complex structures similar to those in the classical world.
Because of this, radiocarbon chemists are continually developing new methods to more effectively clean materials.These new techniques can have a dramatic effect on chronologies.With the development of a new method of cleaning charcoal called ABOx-SC, Michael Bird helped to push back the date of arrival of the first humans in Australia by more than 10,000 years.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.