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Introduction
The principles (simplified) behind this type of dating are the following: there are three isotopes of carbon, 12C, 13C and 14C (radiocarbon). 12C and 13C are stable isotopes, 14C is radioactive and thus, unstable. It is produced in the upper atmosphere through the collision of cosmic rays with nitrogen atoms (14N). 14C becomes part of the global carbon cycle and is distributed among the various reservoirs, i.e. land, oceans, lakes, etc. 14C is assimilated by plants during photosynthesis at an almost fixed ratio to 13C and 12C. Once an organism dies it becomes isolated from the 14C source. The "14C clock" now starts because of radioactive decay and the consequent changes in ratio of 14C to 13C and 12C. This change in ratio over time can be used to measure the age of organic samples. Measurable samples have ages of between 150 and 50,000 years old.
Plant macrofossils, charcoal, wood, peat, seeds, cloth, paper, leather, soil, bone and ivory make up the palette of sample types that we deal although basically, if it's organic it can be dated. In addition, shales (carbonates), lime mortar and some secondary carbonates in sediments and soils may be suitable for dating.
Scientific collaboration
Within the framework of a scientific collaboration: if more than 13 samples are submitted together the price is CHF 375.- per sample, if 5 or more samples are submitted at one time the cost is CHF 450.- per sample. Single samples (less than five) cost CHF 565.- each.
Private institutions and customers (Samples from Switzerland need to add 8% VAT)
If more than 13 samples are submitted together the price is CHF 450.- per sample, if 5 or more samples are submitted at one time the cost is CHF 540.- per sample. Single samples (less than five) cost CHF 680.- each.
Our usual turnaround time is from 3 to 8 weeks (excluding any major accelerator maintenance).