Carbon 14 dating pyramids
Scientists have developed calibration techniques to adjust for these fluctuations.
Second, the 1995 dates vary widely even for a single monument.Other useful radioisotopes for radioactive dating include Uranium -235 (half-life = 704 million years), Uranium -238 (half-life = 4.5 billion years), Thorium-232 (half-life = 14 billion years) and Rubidium-87 (half-life = 49 billion years).The use of various radioisotopes allows the dating of biological and geological samples with a high degree of accuracy.The earliest experiments in radiocarbon dating were done on ancient material from Egypt. Libby’s team obtained acacia wood from the 3rd Dynasty Step Pyramid of Djoser to test a hypothesis they had developed.Libby reasoned that since the half-life of C years, the Djoser sample’s C14 concentration should be about 50% of the concentration found in living wood (for further details, see Arnold and Libby, 1949). Subsequent work with radiocarbon testing raised questions about the fluctuation of atmospheric C14 over time.