I`ve used the nsi opal shimmer in gel and it works fine ... I actually got the idea from an nsi magazine design idea where they had used it with the balance gels..they picked up some gel on the brush then dipped it in the opal shimmer and used it over the whole nail...I have just mixed some in a small pot with builder gel and use it whenever I need to.... the strata illuminations kit has some lovely opal glitter and pearly shimmer additives in it ..i love the white pearl mixed with white gel for a pearl french looks really nice and the rose gold as a topcoat is popular with my clients lovely pink with a pearly gold through it...here`s the link if anyone is interested ..http://www.creativenailplace.com/Tech_pages/strata_kits.htm