Formula X A Little Sexy Nail Lacquer ($10.50 for 0.40 fl. oz.) is described as a “pearl light periwinkle.” It’s a softened, medium-dark periwinkle blue with a metallic finish. It was opaque in a single coat (which is what is shown in the swatches), but the consistency is noticeably thick. The metallic finish is very unforgiving if you don’t let it completely dry on the first coat before applying additional coats, and it tends to look best with a single coat, because it has the least amount of visible brush strokes. Illamasqua Cameo (P, $17.00) is brighter, no shimmer (cream). Chanel Sky Line (LE, $27.00) is much lighter but had a metallic finish/slight muted quality to it. China Glaze Modify (LE, $7.50) is similar without a top coat. See comparison swatches / view dupes.