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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) or the rock saws in the splitting room. There should be no pits or jagged corners. Put the rock into a labeled beaker (Figure 3) and polish . Before polishing the next sample, clean the diamond disc with a dressing stone. Do this for all samples and then move on to 'Cleaning Samples'.
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