Carbon dating cannot give accurate numbers if the sample is younger than 150 years or older than 50,000 years. The inaccuracy for material younger than 150 years is ascribed to changes in the ratio of <SUP>14</SUP>C to <SUP>12</SUP>C in the atmosphere.<ref>http://www.talkorigins.org/indexcc/CD/CD011.html</ref> | Carbon dating cannot give accurate numbers if the sample is younger than 150 years or older than 50,000 years. The inaccuracy for material younger than 150 years is ascribed to changes in the ratio of <SUP>14</SUP>C to <SUP>12</SUP>C in the atmosphere.<ref>http://www.talkorigins.org/indexcc/CD/CD011.html</ref> |