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Icon Muschel/Schnecke


Mussels and snails have a carbonate shell, usually aragonite or calcite. They also survive adverse storage conditions in which other organic material decomposes. During their lifetime the shell is formed by carbon and minerals mainly provided through their died. This means, however, that they convert (old) carbon from their environment and thus show an apparently higher age at 14C age than their actual calendar age. This age shift is called reservoir age and can only be determined if an contemporary organic material from the immediate environment can also be dated. By analysing stable isotopes and other elements, it is also possible to reconstruct environmental conditions with the help of shells and snails.

Sample properties

The sample does not require any special requirements. Even fired shells can be dated and show no difference to unfired ones. Ideally, the complete shell is present and a malacologist has determined the species. At the very least, the place of origin should be communicated, as the reservoir-age shift is species-specific, but also varies in time and place.


At least 50 mg is required for dating molluscs. If sediment should adhere, the sample quantity must be correspondingly larger or, ideally, the sediment itself must be removed before sending in the sample.