Sample submission

If you would like to submit samples to the radiocarbon dating laboratory please contact radiocarbon emailr Stewart Fallon  to obtain a sample submission form. As a small laboratory we are flexible, accepting a wide range of sample types. However, during particularly busy periods we may exceed our 4-5 month turnaround time. If you contact us we can warn you of potential delays prior to submission. We encourage interested students to help prepare their own samples and learn a little more about the radiocarbon dating process. Again, please contact us if you are interested.

Here are some basic guidelines for selecting samples;

  1. Select sample;
    • Consider how well your sample is associated with the event you are trying to date (Table 1).
    • Consider the inbuilt age of your sample (Table 1).
    • Identify your sample to species level wherever possible, and photograph if required.
    • Wherever possible select single entities such as individual fragments of charcoal or single shells. Charcoal can easily fall apart, so please note on the sample submission form whether the sample was originally a single charcoal fragment.
    • If you suspect samples are poorly preserved and may fail the radiocarbon pretreatment, include a backup sample. This is particularly important if you are submitting charcoal or bone from tropical climates.
    • Some laboratories use 14C as an isotopic marker. These samples are highly enriched in 14C and are capable of severely contaminating laboratories and samples making dating impossible. If your laboratory has been involved in tracer 14C studies at any time in the past, please do not send any samples until you have spoken to us.
  2. Package sample;
    • If possible, dry the sample to avoid fungal growth during transport.
    • Samples can be packaged in clean glass or plastic vials or in plastic sample bags. Label clearly with your sample name.
    • Aluminium foil can be used to wrap charcoal to stop it from crushing during transport and storage. Note that aluminium foil reacts with acid and alkali and will corrode rapidly, potentially contaminating your sample. If you are submitting sediments, please do not wrap in foil.
  3. Fill in sample submission form;
  4. Send sample;
    • If you are sending samples from outside Australia, please let us know to discuss potential quarantine issues.
    • Send to:

Prof. Stewart Fallon
Research School of Earth Sciences, The Australian National University
Building 142 Mills Road, Acton, ACT 0200, Australia

We have a 4-5 month sample turnaround.

Table 1; Waterbolk (1971, Proceedings of the Prehistoric Society) outlined two simple criteria which should always be considered when selecting samples.

Association of the sample dated with the archaeological event of interest

Inbuilt age of the sample

Full certainty: Direct association e.g. if dating a human burial it is best to date the human bone.

None (0-1 year), e.g. seed, leaf, bark or nut and Negligible (<20 years), e.g. bone of an animal with a fully terrestrial diet, filter feeding marine shells from an area where the ΔR has been well established.

High probability: Functional relationship e.g. when dating human activity within an occupation level it is good to date charcoal from a hearth feature.

Decades (<100 years), e.g. charcoal from a short-lived tree

Probability: quantity and size of organic materials and diagnostic artefacts argue in favour of a relationship e.g. a charcoal concentration when dating human activity within an occupation level.

Centuries (>100 years), e.g. charcoal from long lived species, humans eating a diet rich in freshwater resources; shells of marine molluscs which are grazers or deposit feeders

Reasonable probability: as with ‘3’ but the fragments are small and scattered.

Unknown source of carbon, e.g. sediment, travertine, freshwater or terrestrial mollusc shell.

The laboratory typically measures the radiocarbon age of 1mg carbon graphite targets, but we are capable of measuring smaller samples where necessary. If you would like to date particularly small samples (<300 μg graphite) please discuss the possibilities with us prior to sample submission. If possible, submit enough material for two or more radiocarbon dates. This will allow duplication of results if required.

Table 2; Typical sample sizes of common materials. Larger samples are often required for older (or very contaminated) samples because harsher pretreatments are necessary.

Sample type

Bone and dentine

Charcoal

Wood

Shell/Coral

Sample size for samples
< 30 ka

200 – 1000 mg

5 – 20 mg

5 – 20 mg

15 mg

Sample size for samples >30 ka

200 – 1000 mg

100 mg

50 mg

100 mg

Example sample size

1000 mg

8 mg

16 mg

90 mg