Methods for dating artifacts

23-Oct-2017 19:33

First, any instrument which is built to measure radiocarbon has a limit beyond which it cannot separate the signal due to radiocarbon in the sample from the signal due to background processes within the measuring apparatus.Even a hypothetical sample containing absolutely no radiocarbon will register counts in a radiocarbon counter because of background signals within the counter.Long tree-ring chronologies are rare (there are only two that I am aware of which are of sufficient length to be of interest to radiocarbon) and difficult to construct.They have been slowly built up by matching ring patterns between trees of different ages, both living and dead, from a given locality.For this reason special precautions need to be exercised when sampling materials which contain only small amounts of radiocarbon.Reports of young radiocarbon ages for coal probably all stem from a misunderstanding of one or both of these two factors.

methods for dating artifacts-23methods for dating artifacts-38methods for dating artifacts-86methods for dating artifacts-16

The second characteristic of the measurement of radiocarbon is that it is easy to contaminate a sample which contains very little radiocarbon with enough radiocarbon from the research environment to give it an apparent radiocarbon age which is much less than its actual radiocarbon age.

The shells of live freshwater clams can, and often do, give anomalous radiocarbon results.

However, the reason for this is understood and the problem is restricted to only a few special cases, of which freshwater clams are the best-known example.

It is not difficult to see how such a claim could arise, however.

There are two characteristics of the instrumental measurement of radiocarbon which, if the lay observer is unaware, could easily lead to such an idea.

The second characteristic of the measurement of radiocarbon is that it is easy to contaminate a sample which contains very little radiocarbon with enough radiocarbon from the research environment to give it an apparent radiocarbon age which is much less than its actual radiocarbon age.

The shells of live freshwater clams can, and often do, give anomalous radiocarbon results.

However, the reason for this is understood and the problem is restricted to only a few special cases, of which freshwater clams are the best-known example.

It is not difficult to see how such a claim could arise, however.

There are two characteristics of the instrumental measurement of radiocarbon which, if the lay observer is unaware, could easily lead to such an idea.

I am not aware of any authentic research which supports this claim.