Con this case, it is well known that (1) the thickness of the surface alteration layer is variable, (2) the preparation of verso thin section requires a small tomo but a suitable surface and (3) an accurate chemical analysis may require verso variable volume depending on the chosen technique.
Sopra this case, the researcher ple that shows the cross-section
Archaeometric analyses can move along the path of non-destructiveness or destructiveness. Between these two end-members, different levels of destructivity and accuracy can be achieved (e.g. highly destructive, minimally-destructive). Provided the same quality of the results obtained, the most obvious approach would be that of non-destructiveness; however, it should be emphasised that, often, non-destructive techniques cannot provide sufficiently accurate or comparable results puro those obtained with destructive methods. Therefore, on the one hand, the researcher risks collecting a lot of quick, cheap and non-destructive datazione that cannot provide unquestionable answers and, on the other hand, tempo inaccuracy can lead sicuro verso waste of time and money.
Therefore, the choice of analytical techniques should first find per balance between the accuracy requirements of quality research and the conservation needs and then direzione sampling onesto the selection of suitable samples. Mediante this regard and based on what has been said previously, it is good to underscore that sampling does not necessarily involve the physical taking of material. Mediante the case of non-destructive techniques, sampling may simply address the selection of the analysis spots.
To conclude, while before proceeding with sampling, it is necessary to collect all available data from any field of study; during sampling, it is mandatory to properly record and document all phases and, after sampling, it is required to remain open and flexible to answer new questions that ples, the overall research should record the various actions and use a critical survey. This survey should be equipped with specific signs that provide a cartographic mapping functional to sampling. Regardless of the use of new technologies for the graphic representation of historical buildings, we should create standardised protocols to record sampling through, mobili jackd for example, a precision topographic positioning.
Therefore, the sampling methods will be crucial sicuro obtain verso suitable sample while observing the fundamental principle of conservation, or in other terms, of minimum sampling
Per sampling of pigments is carried out primarily based on colours. Con this way, by counting the number of colours visible sopra the painting, the number of samples esatto be investigated is also obtained. Con large-scale paintings such as wall paintings, the sampling of per single sample verso colour may prove insufficient. Therefore, it will be necessary sicuro carry out multiple samplings for each colour onesto evaluate any changes. This reasoning is valid both mediante the case of natural and artificial pigments, as it provides the possibility of identifying different technologies and/or provenances.
When the analysis involves non-destructive instrumentation, it is undoubtedly desirable sicuro consider verso large increase per the spots preciso be analysed. When, on the other hand, the research question requires the use of destructive investigations, the number of samples will adapt esatto the minimum necessary and will possibly be taken con the least exposed portion.
For the study of the painting technique, there is an additional difficulty, as the analysis needs sicuro go beyond the pictorial lungometraggio, sopra order to reach the preparatory layer. The first method does not necessarily damage the artefact but is not always resolutive, while the second has the advantage of ensuring an exhaustive response but is destructive. The researcher must, therefore, choose the first or second method based on conservation needs. Verso third option is to be considered when the analysis concerns mobile artwork and consists of instruments with per higher penetration capacity than conventional techniques, such as Raman or portable Incognita-ray fluorescence.