{"id":661,"date":"2023-10-27T14:08:44","date_gmt":"2023-10-27T12:08:44","guid":{"rendered":"https:\/\/ceza.de\/?post_type=methods&p=661"},"modified":"2025-07-10T09:34:13","modified_gmt":"2025-07-10T07:34:13","slug":"c-14-dating","status":"publish","type":"methods","link":"https:\/\/ceza.de\/english\/cezapedia\/methods\/c-14-dating","title":{"rendered":"14C-Dating"},"content":{"rendered":"\n

Dating by radiocarbon (14<\/sup>C) is a universally applicable dating method in archaeology and in environmental and geosciences. The method can be applied to a variety of organic materials for age determinations of up to 50,000 years before present. This and much more…<\/p>\n\n\n\n

Application<\/h2>\n\n\n\n

Radiocarbon is present within many materials, hence all of them can be dated \u2013 from plants, wood, charcoal, bones, skin, and hair, to products such as paper, cloth, leather, and canvas.<\/p>\n\n\n\n

Radiocarbon dating can also be applied to carbonates such as shells, speleothems or carbonates in groundwater, ocean water, river, and lake water. In addition, 14<\/sup>C-dating is applied in areas outside of archaeological research such as authenticity testing, forensics, and ivory certification (CITES). The possibility of determining the proportion of renewable (biogenic) raw materials in products of the chemical industry (e.g. biofuels and bio-oils, cosmetics, plastics) or the detection of artificial additives (e.g. aromas) in areas of the food industry, demonstrates that the application spectrum in which this method can be applied, goes far beyond dating.<\/p>\n\n\n\n

The analysis of today\u2019s atmospheric radiocarbon content reflects the usage of fossil energy (fuels, oils) and their link to climate change.<\/p>\n\n\n\n

Basics<\/h2>\n\n\n\n

Three carbon isotopes exist in nature \u2013 12<\/sup>C, 13<\/sup>C and 14<\/sup>C. The latter is radioactive and decays in the course of time. The decay rate of the 14<\/sup>C isotope is fixed and thus provides information on the lifespan of organic material. As soon as an organic material is cut-off from carbon exchange with the environment (e.g. by harvesting a plant or death of an animal), the amount of this carbon isotope continuously decreases. After 5,730 years, only half of the initial 14<\/sup>C is still present in the sample material, and after ten half-lives the remaining 14<\/sup>C level can no longer be detected with today\u2019s instruments. Therefore, age determination is possible up to approx. 50,000 years (conventional 14<\/sup>C years) – simply by analyzing the carbon isotope ratio in a sample.<\/p>\n\n\n\n

However, 14<\/sup>C analysis is far from \u201esimple\u201c, considering that the fraction of 14<\/sup>C is extremely low: The ratio of the isotopes 14<\/sup>C to 12<\/sup>C is only about 10-12<\/sup>, and in an old archaeological sample, for example, it is even smaller. One can imagine the proportion of 14<\/sup>C here as a single hair in relation to all the hair everyone in the world. In this case, the isotope is incredibly rare and requires extreme precision to detect.<\/p>\n\n\n\n

Radiocarbon is formed in earth\u2018s atmosphere by the interaction of cosmic radiation with nitrogen atoms in the air. The resulting 14<\/sup>C immediately binds with oxygen and produces 14<\/sup>CO2<\/sub>, which then passes into plants via the process of photosynthesis. Radiocarbon then reaches humans and animals through the food chain. It is also found in rivers, oceans, soil, and sediments. An exchange between all those carbon reservoirs takes place continuously \u2013 the carbon cycle.<\/p>\n\n\n\n

Limitations<\/h2>\n\n\n\n

The dating limit of 14<\/sup>C-dating is around 50,000 years (conventional 14<\/sup>C years), which lets us look back into the Neanderthal era. Age determinations beyond that are not possible based on radiocarbon. Much younger objects, too, can push the method to its limits: due to the large changes in the atmospheric 14<\/sup>C concentration between 1680 and 1950 caused by highly variable solar activity and the combustion of fossil fuels. As a result, dating with the help of 14<\/sup>C is ambiguous in this time period; a single radiocarbon age yields several possible calendar ages in between 1680 to 1950 after its calibration. It is therefore impossible to identify the correct calendar date that reflects the age of the object by using 14<\/sup>C alone.<\/p>\n\n\n\n

Material formed after 1950 is influenced by man-made 14<\/sup>C, which was produced in the atmosphere during the nuclear-weapons tests in the 1960s. In this case, however, it is potentially possible to date samples with very high precision down to a few years. The method also impresses with its high precision in other respects: in Holocene samples (younger than 10,000 years), for example, it is generally in the range of 0.2 to 0.3 % equivalent to \u00b1 25 to 30 radiocarbon years.<\/p>\n\n\n\n

Sample composition<\/h2>\n\n\n\n

Typical sample quantities are:<\/p>\n\n\n\n