Rafter Radiocarbon Laboratory

Submitting samples for dating

PDF Documents for Download:
Sample Submission Form (48K PDF)
Standard Terms and Conditions (48K PDF)
MAF Import Permit  (1MB PDF)

Inclusion of the MAF Import Permit with the sample documentation and writing the permit number on the outside of the package is all that is required.

1. How to send samples
Where possible, send dry samples. Bacterial activity in wet samples can affect the final 14C age. Use a low temperature oven which has never been used for radioisotope experiments. Cover samples with lightly perforated foil and heat at a temperature of at least 40°C till dry.

Trackable courier despatch or registered post is preferred and samples are acknowledged on receipt by us. Couriers commonly used include DHL and Federal Express but also consider your postal services as they usually have fixed price postage Priority or Express Mail International tracked envelopes or boxes allowing up to some maximum weight. Include on the package label "Samples for Scientific Analysis - no commercial value" and send to:

Rafter Radiocarbon Laboratory
GNS Science
30 Gracefield Road, Gracefield
Lower Hutt 5010
PO Box 31312
Lower Hutt 5040
New Zealand

2. Documentation
All samples should be accompanied with sufficient documentation to identify each individual sample. This would include the nature of the sample material, full name and contact details of the submitter and where applicable additional information for the purposes of invoicing eg. Order numbers

Details of any prior treatment of the sample, such as cleaning, drying, treatment with solvents or preservatives, or any repair work should also be supplied. The relevant information can be supplied via our Sample Submission Form, a copy of which will be mailed or faxed to you on request.

 

IMPORTANT

We cannot avoid the long arm of bureaucracy, and sometimes the bureaucrats are right. Please assist us, and yourself, by observing the following requirements:

• Samples sent from outside New Zealand must be accompanied by a copy of the New Zealand Ministry of Agriculture Import Permit. Failure to do this may result in your samples being confiscated on entry into New Zealand, with subsequent delays before they are released. You will be sent a copy of the Import Permit when you first contact us, and you should not send your samples until you receive the permit.
• Materials such as ivory or coral are covered by the CITES Agreement (Convention on International Trade in Endangered Species). New Zealand is a signatory to the agreement, and sample materials covered by CITES must show an exemption code on the packaging. We can supply you with the appropriate code on request to facilitate the importing of the samples to New Zealand, but you are responsible for arranging the necessary permit to export the sample from the country of origin.

3. Sample Types
Samples can be submitted as:

• Original material for full laboratory processing. Our Sample Preparation Laboratory is experienced in handling a wide range of materials. We can advise you on the suitability of particular types of materials for radiocarbon dating, and we will be happy to discuss with you the most suitable way of taking a sample and packaging it to send to our laboratory.
• Clean CO2 gas sent in break-seal tubes. We can accept 6mm and 9mm outer diameter sealed pyrex or quartz tubes between 16 and 20cm in length. The preferred amount of CO2 is approximately 2mg of Carbon or 4mls of CO2 at STP. For alternate tube sizes up to 15mm outer diameter please contact us. Some ideas for packaging include placing wrapped tubes inside rigid plastic tubing eg. polythene piping. Taping the tubes to bubble wrap at regular intervals and rolling into a cylinder is another option. This can then be placed into a solid cardboard mailing tube or a rigid cardboard box.
• Graphite, ready for insertion into the accelerator ion source. We can advise on the best way of sending the graphite. Generally, it is advisable to send some test samples first, to ensure that your graphite will give a satisfactory output in our ion source.

4. Sample Sizes
Ideally, samples should yield about 2mg of carbon after processing, and the corresponding amounts of sample material are typically as follows:

Material	Amount Required
Bone	150 - 3000mg, (Depending on condition)
Charcoal	30 - 100 mg.
Peat	1 - 3 gm (Depending on carbon content)
Sediments	1 - 3 gm (Depending on carbon content)
Shell & forams	30 mg
Textile	30 mg
Wood	50 - 300 mg

The carbon content of peats and sediments can vary greatly. 90 mg of a peat which has a 10% organic carbon content would yield sufficient material for dating, while a sediment which is only 0.1% organic carbon might require almost 9 grammes. If you are unsure of the carbon content of your sample, please contact the laboratory before submitting so we may discuss size and treatment procedures.

Smaller quantities than those indicated can be handled, but the precision of the results may suffer as a consequence.

5. Reporting Times

Results are reported within eight weeks of receipt of sample and include:

• d13C, measured by stable isotope mass spectrometry (see note at foot of Sample Processing page)
• Conventional radiocarbon age, per-cent modern and D14C, based on the NIST HOxI oxalic acid standard
• Where applicable, calibrated ages based on published tree-ring calibration data

Reporting time may be longer if batches of more than ten samples are submitted or if the nature of the material is such that special processing methods are required.

A special 3-week turn-around service at higher cost can be made available on request, subject to current laboratory workloads.

The total error reported for radiocarbon ages includes counting statistics and instrumental error. For ages less than 10,000 years the error is typically ± 40 years. The demands of a particular study may require an event be timed more precisely than this. In such a situation, an enhanced precision service offering reduced error is available. With enhanced precision, the error is typically less than ± 30 years.

6. Standard Prices: click here