After a couple of test runs, we found mixing the glitter directly into the grout wasn't the effect we wanted. We decided to do the initial grouting, glitter free, and then work the glitter into the the grout after the last sponging. (I used a make up kabuki brush to dab the glitter from a bowl into the grout) We let it set over night, gave the tile a nice buff and the glitter was perfect.My picture doesn't do the end result justice!
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