My childhood nail-biting habit returns from time to time, especially if I’m not wearing any polish. So, on one particularly rough day at work a couple weeks ago, I decided I needed to stop nibbling and quickly brushed on an iridescent top coat that was sitting on my desk. Not only did the paint stop me from picking my nails, but it’s become my new favorite color. Some cool options, after the jump!CND Sapphire Sparkle isn’t an in-your-face polish. In fact, it has more in common with clear than an actual color, and the sparkles are so tiny that they aren’t juvenile; nails shimmer subtly when the light hits them. Annika also tried out an iridescent shade when she got a manicure last week. Essie Main Squeeze, from the 2010 wedding collection, looks nothing like it does in the product shot but offers a step up from clear or pale pink, because the polish looks like a slightly different color depending on the angle. An added bonus about iridescents and opalescents: they tend to fade away gracefully, so you’re never stuck with obviously chipped polish like you are with a bright shade.