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ICP-MS & XRF

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Instrumentation is available for inorganic and speciation analysis on water, as well as soil, rock and plant digests, while geochemical analysis of mineral separates and fused bulk rock samples, as well as U/Pb dating of zircons & monazite, is done by laser ablation ICP-MS. Major and minor elements analysis by XRF.

Click here to request a quotation on Solution or Whole rock analysis.

Solution ICP-MS

Most of the elements on the periodic table, with the exception of C, H, O, N, the halides & inert gasses can be analysed, in the concentration range of hundreds of mg/L to ng/L. Major and minor elements down to mid-ppb values are measured on a Thermo ICap 6300 ICP-AES, while ultra-trace analysis is done on an Agilent 7900 ICP-MS or Agilent 8800 QQQ ICP-MS. Data is quantified with calibration solutions prepared from NIST traceable standards, and quality control procedures according to US EPA guidelines are followed to ensure accuracy of data. Samples can be prepared by the client, or we can do a microwave digestion on a large variety of samples. Please have a look at our sample submission guide for more information.

Laser Ablation ICP-MS

For laser ablation work, a Resolution M-50-LR Excimer laser ablation system from Resonetics is connected to an Agilent 7700 ICP-MS for most of the trace element analysis, while a Thermo Element 2 HR-SF-ICP-MS is connected to Resolution M-50-SE Excimer laser for U/Pb measurements.

Trace elements in bulk rock samples are analysed on polished mounts prepared from XRF fusions. Individual mineral grains can also be mounted and polished for analysis. NIST traceable standards are used for quantification. A mineral separation facility is available, comprising a Wilfley table, Frantz Magnetic Separator, heavy liquid separation, and optical microscopes for handpicking of minerals. Suitable grains for U/Pb measurements are first imaged on the SEM before analysed by LA ICP-MS. Commercial, as well as in-house zircon standards are used.

X-ray Fluorescence Spectrometry (XRF)

XRF is ideal for rapid and accurate whole bulk elemental analysis in rock or soil samples. The gas-flow proportional counting detector and scintillation detector, or a combination of the two, are used to cover the elements fluorine to uranium. Major elements are analysed on a fused glass bead and trace elements are analysed on a powder briquette. A wide range of international (NIST®) and national (SARM®) standards is used in the calibration procedures and quality control (precision and accuracy) for both major and trace element analyses. Detection limits for the elements quoted, depending on the matrix (combination of elements present), are typically 0.5 ppm. Loss on Ignition (LOI) is a test used in XRF major element analysis which consists of strongly heating a sample of the material at a specified temperature, allowing volatile substances to escape or oxygen is added, until its mass ceases to change. The L.O.I. is made of contributions from the volatile compounds H2O+, OH-, CO2, F, Cl, S; in parts also K, Na (if heated for too long); or alternatively added compounds O2 (oxidation, e.g. FeO to Fe2O3), later CO2 (CaO to CaCO3). In pyro-processing and the mineral industries such as lime, calcined bauxite, refractories or cement manufacture, the loss on ignition of the raw material is roughly equivalent to the loss in mass that it will undergo in a kiln, furnace or smelter.