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Polish the rocks with a Breuler diamond disc (Figure 2) until they're completely smooth and round on all edges. The purpose of grinding on a diamond disc is to remove any possible contaminates caused by the drilling mud (or drill bit) along with the rock saws in the splitting room. There should no pits or jagged corners. Put the rock into a labeled beaker (Figure 3) and polish the next sample. Do this for all samples and then move on to 'Cleaning Samples'.
Figure 2. Buehler diamond discs for polishing (use either one, or start with the courser grain and finish with finer grain).
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