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X-Ray Fluorescence Spectrometer Sample Preparation
The analysis of a rock involves many steps. The sample preparation is essential, as any contamination or mistake in this step will lead to erroneous results.
About 500 g of sample are chipped into < ½ inch chips and quartered for homogeneity.
About 100 g are powdered,
sieved and homogenized.
The powders are dried in an oven and carefully weighed to the fourth decimal.
The fused disks are prepared with ignited powders. The Loss of ignition is performed at 1100C.
In the wet Chemistry laboratory, the ignited powder is mixed with Li tetraborate and then fused at 1100 C in the bead maker.
Michael Brewin working with the bead maker.
Fused glass pouring into the casting dish.
Fused disk.
The trace elements are measured on pressed pellets. Dry powder is mixed with cellulose and then pressed with a hydraulic press.
Michael Brewin making a pressed pellet.
Pressed pellet in the hydraulic press.
Pressed pellet.
The concentration of FeO is determined by titration and then entered as a fixed value in the XRF spectrometer.
John Nay is performing a FeO determination on basalt.