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The department has a PANalytical X'Pert Pro MPD xray diffraction instrument (XRD) for identification and quantification of crystalline materials by use of xray powderdiffraction-techniques and clay minerals on oriented specimens.

XRD analyses can be carried out on bulk material (0.5-1 g of dried and finely grinded powder) and on clay specimens (1 smear slide of the clay fraction below 0.002 mm is measured 3 times, using different settings). The clay fraction is concentrated in a process involving repeated sedimentation. Normally 10-15 g of sample is used, depending on moisture and expected clay content. The clay is smeared onto a glass plate. When dried, this clay layer has a thickness of 0.1 mm.

Bulk and untreated clay is normally measured using a 10 minute program in angles within 2-65 degrees.

Ethylen-glycolated and heated (500 degrees of Celcius) clay specimens are normally measured using a 5 minute program in angles within 2-35 degrees.

The following minerals can be identified and quantified in bulk specimens: Magnetite, hematite, pyrite, siderite, apatite, halite, rhodocrosite, dolomite augite, calcite, baryte, jarosite, plagioclase, K-feldspar, aragonite, anhydrite, cristobalite, quartz, gibbsite, gipsum, amphibol, clinoptilolite/heulandite.

The following minerals can be identified and quantified by clay mineralogy: Kaolinite, illite, chlorite, vermiculite, smectite.

Generator settings during analyses is 45 kV and 40 mA.

The anode is of copper and the monochromator on the incoming beam is a germanium crystal.

3 sample holders each having 15 slots makes it possible to automate measurement on 45 samples at a time.