Energy dispersive X-ray microanalysis (EDX) can be used to determine which elements are present in a paint sample.
A scanning electron microscope (SEM) is usually used in EDX. An electron beam falls on the paint sample generating a small amount of X-rays. The X-rays can identify the various elements which are present in the sample.
EDX can show whether a sample contains, for example, chemical elements such as lead, copper, arsenic, tin, antimony, cobalt and chromium. However, this is not sufficient to show which component pigments have been used. EDX must be used in conjunction with optical microscopy in order to find out which pigments are present.