The nail art involves applying shards of foil to the nails, giving an illusion of shattered glass. Foils don’t work with regular polish, so a glass manicure should involve gel. Most commonly, you’ll see a glass manicure with a clear or neutral base color and then chrome foils over top. Chrome, or, what Zoey, a nail artist at New York’s Vanity Projects salon, calls “aurora” foils for their reflective quality like the Northern Lights, shining different colors when the light hits.