Radiocarbon (14C) dating is used to determine the age of an object or material containing organic carbon by measuring the proportion of carbon 14 (14C) it contains.
It is assumed that the carbon in the material was assimilated from the environment while the organism that gave rise to the material was alive and the proportion of the three isotopes of carbon inside remains the same. Once the organism dies, the amount of 14C slowly decreases at a known rate (radioactive decay) relative to the non-radioactive, or stable isotopes of carbon in the material.
Radiocarbon dating provides an objective method of determining time ranges within which an object may be placed. Since it dates the material, and not necessarily the process that the material may have been subjected to, ie. carving in the case of wood, weaving in the case of textiles, the age measured must be interpreted in light of all available evidence to determine authenticity.
Established in 1986, Paleo Lab is based in Japan and the leading radiocarbon dating lab in Asia working to full International Quality assurance standards ISO 17025.
Until its cooperation with Antique Authentication, Paleo Lab’s focus was academic and research based working mostly with archeological and geological samples for universities, institutions and museums in China, Korea, Japan and in the US. Additionally, they work within the fields of anthropology, paleontology, architectural history, environmental studies and hydrology, as well as with the certification of industrial materials.
In Asia, with the exception of Japan and Korea, Antique Authentication is the sole representative for Paleo Lab.
Any object made from organic material that contains carbon is suitable for radiocarbon dating. For example, objects made from wood, textile, ivory, bone, shell, paper and lacquer can be tested.
Ideally, samples should yield approximately 2 mg of carbon after processing, and the corresponding amounts of sample material to be taken are typically as follows:
Radiocarbon (14C) is one of the radioisotopes produced in the atmosphere by cosmic rays coming into earth’s atmosphere. The 14C atoms produced exist mainly as carbon dioxide molecules in abundant levels to the stable carbon isotope 12C, i.e. 14C/12C ratio of 1.2 x 10-12. As carbon atoms in the atmosphere are incorporated in living material by photosynthesis, 14C atoms also move into the living material in the similar isotope ratio 14C/12C of 1.2 x 10-12. When the living material dies, the 14C atoms contained in the living material start to decrease by the radioactive decay process. The half-life of 14C is 5730 years, and the ratio in the present abundance of the 14C atoms in the sample material after decreasing by the decay process to its initial abundance is translated as the age that passed since the time of death of the living material. This is the principle of 14C dating.
Pretreatment is a multistep process of isolating the required carbon fraction from a carbonaceous sample for radiocarbon dating. In most cases, the fractions desired for 14C measurement are those from molecules indigenous to the organism when it was alive, and isolating this native carbon means removing any contaminating organic material that may have been introduced during sample preservation after its death.
Within an average of six weeks, clients will receive a clear and concise summary, in non technical language, on the sample treatment procedures and accelerator mass spectrometry results with a calibration report which includes confidence limits of the assigned calendar age ranges. In some cases, an urgent service of four weeks can be provided.
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