Samples are first mixed with lithium tetraborate and vitrified into circular glass disks by a propane fluxer. They are then irradiated by x-rays emitted from an internal X-ray tube (Rh-anode). The characteristic fluorescence emission (unique for each element) is dispersed by a single crystal and measured by a scintillation detector or a flow detector. Elemental composition (in the form of oxides) are expressed in wt%.
The XRF spectrometer is equipped with six different crystals to cover the fluorescence emissions from elements range from oxygen to uranium.