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The following technique is modified from the U.S. Geological Survey Open-File Report 01-041, A Laboratory Manual for X-Ray Powder Diffraction. For a very small amount of sample material (i.e., end of a tooth pick), samples may be ground to a fine talc-like powder and smeared onto one of the quartz disk or zero background inserts. Although not useful for semiquantitative analysis, this method is useful for rapidly determining bulk mineralogy.
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