AMS Stable Carbon and Nitrogen Isotopes

Measuring Stable Carbon and Nitrogen Isotopes (δ13C and δ15N)

Sample size requirements vary per material and if pretreatment is requested (see below)
Recommended container
Ziplock Bags (place in Aluminum foil if sample is small or can be crushed during shipment)
Please send your samples in small boxes instead of envelopes to protect the samples.

For water samples – Use a small vial with no prior use. Fill to the top with no headspace. Send to the lab in a sturdy cardboard box with sufficient packing to prevent breakage during shipment.

Turnaround time – 7 business days for pretreated samples and 14 business days for samples that still need pretreatment

Note – Our laboratory also provides d13C and d15N measurements in conjunction with Carbon-14 dating. We routinely provide d15N testing on bone collagen. For other material types, please contact us for discussion.

Our AMS dating fees for bones are inclusive of d13C measurements, d15N measurements (except cremated bones), quality assurance reports, calendar calibration when applicable, and 24/7 web access to past results and pending analyses. Collagen extraction fee applies in addition to the standard price. If the collagen is not suitable for radiocarbon dating, the analysis can be cancelled.

The d13C and d15N ratios are measured using an isotope ratio mass spectrometer (IRMS). We may not be able to provide d15N measurements for charred or burned bones depending on the sample quality. Please contact us before submitting burned bones.

Pretreatment – It is important to understand the pretreatment applied to samples since they directly affect the final result. Contact us to discuss.

Recommended Sample Sizes

The following are minimum size recommendations and may not prove to be sufficient in every instance. If you are submitting samples for both d13C and d15N analyses, please double or triple the weights specified below.

Please use this data sheet when submitting samples for either d13C or d15N analyses NOT in conjunction with C14 dating.

Please contact us at lab@radiocarbon.com if you are in doubt about the suitability or weight of your sample.

MaterialUnpretreatedPretreated
Bone/Antler/Charred Bone2-10 grams *2 milligrams
Charcoal10-20 milligrams *5 milligrams
Dung10-20 milligrams *2 milligrams
Fish Otoliths (d13C only)7-10 milligrams *2 milligrams
Forams (d13C only)5-10 milligrams **2 milligrams
Hair20-50 milligrams *2 milligrams
Insect (Chitin)20 milligrams *2 milligrams
Leather50-100 milligrams *2 milligrams
Organic Sediment/Gyttja2-10 grams *20 milligrams
Peat50-100 milligrams *2 milligrams
Plants/Seeds10-20 milligrams *2 milligrams
Pollen20 milligrams *4 milligrams
Shell / Coral / CaCO3 (d13C only)20-50 milligrams *2 milligrams
Textile20-50 milligrams *2 milligrams
Water for DIC extraction (d13C only)1-2 milliliters (maximum pH ~8) ***
Wood10-20 milligrams *2 milligrams

* Minimum quantity requested is 300 micrograms of carbon after pretreatment.
** This is the recommended quantity. For minimum amount, contact us for discussion.
*** Use small vial and fill to the top with no headspace.