The methodology followed for a specimen microscopic analysis by means of the most important techniques are described in this slide.
First, specimen requires a direct observation in order to decide if a pretreatment before characterisation is needed.
In some cases the specimen has such a small dimension that make impossible its handling. For this reason, a correct cutting must be decided according to the kind of material. For instance, soft or powdery materials must be cut at low temperatures by means of a microtome.
In other cases it is not possible to observe directly the specimen by the microscope because its irregular surface. Then, grinding and polishing procedures must be followed. In other cases, there are some analytical techniques where it is necessary a conductive feature of the sample (polymers), and therefore the sample must be cut in thin sections and coated with a conductive material. This is the case of Scanning Electron Microcopy analysis.