Sample Types and Quantities
The following table summarizes the recommended ideal and minimum weights for different sample types. For solid materials, this means the weight of the dry sample. If you did not find your material in the table or you are not sure about the material, please contact the laboratory. Dating samples with weight lower than the minimum carries an increased risk of failure. With the consent of the client, it is possible to try to date such samples as well.
|Sample type||Weight (mg)||Notes
|wood||50||15||For rotted or water-soaked wood, the minimum weight must be increased.
|charred sample||20||5||For example, charcoals, charred macro-residues.
|carbonates||150||50||For example, mollusk shells, mortar, sinter.
|bones||1000||500||Depending on the condition of the bone (see text bellow the table).
|plant macro-residues||200||20||For example, peat, seeds, pollen, concentrates, plant parts|
|leather, horn, silk, hair, woolen fabrics||30||15|
|art objects||Contact us|
|lipids in pottery||Contact us|
In radiocarbon dating of bones by collagen isolation and purification, it is difficult to ensure sufficient decontamination of highly degraded samples from interfering humic acids, which are very tightly bound. For this reason, the laboratory has implemented a bone quality assessment procedure. Several parameters determined during the processing of these samples are used for this evaluation. The dating results of low-quality samples are rather indicative, and the laboratory, therefore, recommends caution when handling such results. Bone samples with collagen concentrations of less than 1% are labelled by the CRL laboratory as undatable, as is the case with other radiocarbon laboratories.