Among the artifacts from the University of Chicago’s Oriental Institute that Prof.
The resulting release of carbon dioxide is fed to an accelerator mass spectrometer, which measures the decay of radioactive carbon 14the more the carbon 14 has decayed, the older the object is.Over the past 20 years, chemist Marvin Rowe of Texas A&M University has developed a nondestructive method for carbon dioxide extraction.After a creature's death the isotope would slowly decay away over millennia at a fixed rate.Thus the less of it that remained in an object, in proportion to normal carbon, the older the object was.The older a sample is, the less (the period of time after which half of a given sample will have decayed) is about 5,730 years, the oldest dates that can be reliably measured by this process date to around 50,000 years ago, although special preparation methods occasionally permit accurate analysis of older samples.
The idea behind radiocarbon dating is straightforward, but years of work were required to develop the technique to the point where accurate dates could be obtained.
Research has been ongoing since the 1960s to determine what the proportion of in the atmosphere has been over the past fifty thousand years.
The resulting data, in the form of a calibration curve, is now used to convert a given measurement of radiocarbon in a sample into an estimate of the sample's calendar age.
Precisely dating archaeological artifacts is not as easy or harmless as it might seem.
The most common method, radiocarbon dating, requires that a piece of an organic object be destroyedwashed with a strong acid and base at high temperature to remove impurities, and then set aflame.
The artifact, more than 2,000 years old, dates to the Egyptian Ptolemaic period.