X-ray fluorescence, or XRF, is powerful, versatile technology. A handheld XRF instrument can analyze the elemental composition of any material—with quantitative results in the case of homogenous samples—with an element range from Mg (magnesium) to U (uranium). Handheld XRF technology is best in terms of ease of analysis and low limits of detection for elements from K (potassium) to U (uranium).
The elements Mg (magnesium) through Cl (chlorine) are also within the analysis range of handheld XRF, but a handheld instrument needs to have either a silicone drift detector or a helium or vacuum purge in order to detect these elements. Additionally, the limits of detection (LODs) for these light elements will be relatively low.
Most handheld XRF analyzers cannot detect elements lighter than—or with a lower atomic number than—magnesium. However, the Bruker Tracer with SD detector is said to be able to detect Na (sodium).
Another limitation of handheld XRF—and XRF in general—is that you need a homogeneous sample in order to get accurate quantitative data. For this reason XRF is a great quantitative method for samples such as alloys or homogenized soil or geological samples. However, samples that are coarse, have lots of inclusions, multiple layers, or are non homogeneous in some other way are not ideal for quantitative XRF analysis. However, you can still get lots of information from such samples; qualitative or semi-quantitative information can be obtained, which tells you what elements are present in your sample and in what relative quantity respectively.