The radioactive carbon isotope is no longer replenished; it only decays.Scientists have calculated the rate at which C14 decays.Test results from Middle Kingdom pyramid (Senwosret II).
We wanted to use science to test the accepted historical dates of several Old Kingdom monuments.
One radioactive, or unstable, carbon isotope is C14, which decays over time and therefore provides scientists with a kind of clock for measuring the age of organic material.
We also have fair agreement between our radiocarbon dates and historical dates for the Middle Kingdom.
Eight calibrated dates on straw from the pyramid of Senwosret II (1897-1878 BC) ranged from 103 years older to 78 years younger than the historical dates for his reign.
Scientists have developed calibration techniques to adjust for these fluctuations.
While alive, all plants and animals take C14 into their bodies.
By measuring how much C14 remains in a sample of organic material, we can estimate its age within a range of dates.
Samples older than 50,000 to 60,000 years are not useful for radiocarbon testing because by then, the amount of C14 remaining is too small to be dated.
In spite of this discrepancy, the radiocarbon dates confirmed that the Great Pyramid belonged to the historical era studied by Egyptologists. Koch Foundation supported us for another round of radiocarbon dating.
We broadened our sampling to include material from: We also took samples from our Giza Plateau Mapping Project Lost City excavations (4th Dynasty), where we discovered two largely intact bakeries in 1991.
The numbers of C14 atoms and non-radioactive carbon atoms remain approximately the same over time during the organism’s life.