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Before being crushed in the X-Press, hard rock samples for ICP analysis are polished (Figure 1.1 and 1.2) and cleaned in a sonic bath at least three times (for 10-15 minutes each): the first round of cleaning is with isopropyl alcohol and the following rounds are with DI water (Figure 1.3, see ICP Sample Preparation for further details). Hard rock samples for XRD analysis do not usually need to be polished before being crushed.
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