Materials, archaeological elemental form

Neutron activation analysis is valuable as a non-destructive form of analysis. It can be used without fear of damaging or destroying the material being tested. It is also a very precise form of analysis, permitting the detection of very small quantities of an element. One application that illustrates these strengths is in the analysis of archaeological materials that are too fragile or too valuable to expose to other analytical techniques. 

Note that any specihc application tends to determine the additional sample preparation required, before the start of the CF-MS measurement, so most applications need to be considered individually. For example, there is very little S in living bone (it is mainly in methionine), while during burial, iron pyrites is often formed. Consequently, much applied archaeological analysis must consider the effects of contamination and alteration during burial and devise appropriate protocols for the elements in question and from the material being sampled. 

Figure 32-9 illustrates that neutron activation is potentially applicable to the determination of sixty-nine elements. In addition, four of the inert gases form radionuclides with thermal neutrons and thus can also be determined. Finally, three additional elements — oxygen, nitrogen, and yttrium — can be activated with fast neutrons. A list of types of materials to which the method has been applied is impressive and includes metals, alloys, archaeological objects, semiconductors, biological specimens, rocks, minerals, and water. Acceptance of evidence developed from activation analysis by courts of law has led to its widespread use in forensic chemistry. Here, the high sensitivities and nondestructive aspect of the method are particularly useful. Most applications have involved the determination of traces of various elements. ... 

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