Tips for collecting Radio Carbon samples in Archaeology

The following is a modest collection of tips for collecting Radio Carbon and AMS samples coming for my personal experience:

Samples collected at the field :

• Be sure you are selecting a sample from the layer you want to know the absolute date


• Select the sample with bigger volume (carbon, bone, shell with bigger size)


• Select samples without or with a minimum penetrated roots, ants or any other penetrating things


• Pack samples with plenty aluminium foil and put inside double labeled plastic zip-bag


• Include all information about position, layer, test pit or trench information outside the bag


• Take a record as usual (photo, diagrams, notebook info, etc)

Samples selection by type

Skeleton (collagen) samples:

- On skeleton samples I recommend a sample from a massive bone (femur, tibia, etc) by making a transverse cutting rather than to take a small bone (ribs, hand, etc).

- Alternatives: we have options like a teeth that also provide a good opportunity or an articular foot bone.

- All option should include the cortex rather than porous broken bones

- From all type of samples, human bones are the most confident type of sample. They are just the man or woman who lived just there or food eaten at that moment! other samples are always indirect or associated.

Carbon Samples:

- Take samples with a minimum or without root penetration where is possible. Try Radio Carbon dating instead AMS when you suspect root or mold penetration. Radio Carbon work averaging the content versus AMS that select a part of the sample making possible a big error if the sample took a big part of a modern root.

-Take the carbon samples with fine tools

- Don't worry if you have to take the sample at naked hand but be sure you use aluminium foil

- Carbon are the second option in confidence for dating context. Reason? carbon can be move by up and down by natural animals (worn, ants, etc) and usually are subject to mold and root penetration into the porous matrix making impossible its removing. Bones are relative more easy to remove at the laboratory.

Shell Samples:

- Shell are easy to identify and clean. Only take few of then with reasonable size.

- Shell are less confident that the others two type. Why? shell could be used by human or surviving on the grown for centuries or even thousand of years and then finally discarded on the context. On the other hand, in my personal opinion, some labs appear to by uncalibrated for tropical shells, making dating looks older than actually is (some cases a thousand of years older tan a sample from human bone in the same layer).