Geoanalytical Laboratory (XRF and XRD)

Location:  41.G63
Contact:   Lloyd White

The Geoanalytical Laboratory contains a ThermoFisher ARL Equinox 1000 X-ray diffractometer (XRD) commissioned in 2019 and a Spectro Xepos X-Ray Fluorescence (XRF) spectrometer commissioned in 2006.

The XRD is used to identify the mineralogy and crystallography of powdered samples, while the XRF is configured for routine analysis of major elements and trace elements within rock and sediment samples (typically using glass fusion disks and powdered pressed pellets). We have the capability to prepare samples for XRF and XRD analyses within our sample preparation laboratory. The laboratory is open for internal, collaborative and commercial use. Costs depend on the type of analyses, the amount users are involved and whether the work is collaborative or commercial.

XRF

The XRF system is a desktop Spectro XEPOS energy dispersive spectrometer. It has a 12-position carousel sample loader and is used to measure the major and trace element composition of silicate materials. Our routine analyses focus on high-accuracy high reproducibility of major and trace element analyses on igneous, metamorphic and sedimentary rocks and soils. Major element analyses consist of SiO2, Al2O3, Fe2O3, MgO, CaO, Na2O, K2O, TiO2, MnO and P2O5. Trace element analyses typically consist of Cl, V, Cr, Co, Ni, Cu, Zn, Ga, S, Ge, As, Se, Br, Sr, Y, Zr, Nb, Mo, Cd, Sn, Sb, Cs, Ba, Hf, Ta, W, Hg, Pb, Bi, Th, U. Unknown results are routinely compared with internationally recognized standard reference materials.

XRD

The XRD system is a 2019 ThermoFisher ARL Equinox 1000 configured using a copper x-ray tube and equipped with a 30-position sample loader. The sample that is being analysed is rotated during spectra acquisition. The curved detector design means that the diffractogram is generated across the spectrum at the same time, with longer count times leading to higher resolution data. Data that are acquired can be examined using Match! and compared with crystallographic databases (PDF and the open-access COD). Rietveld refinement can be performed using MAUD or SIROQUANT.