MANICURES aren’t known for being everlasting. They chip. They smudge. Sometimes a nail is ruined even before you get home from the salon.

So it was curious to hear Michelle Mismas, who writes the nail-focused blog alllacqueredup.com, describe the indestructibility of a recent manicure. “When I was wearing it, I beat my hands up, and I couldn’t get a scratch,” she said by phone. “I was banging into things on purpose to see if I could trash it.”

Two weeks out, her dark raisin hue was the same shiny perfection. How? She was wearing Shellac, a soak-off hybrid between a gel and polish that will make its debut on May 1 in 2,000 salons nationwide. (She had a free sneak peek during New York Fashion Week in February.)

Image The shellac is applied to nails like normal fingernail polish. Credit... Donna Alberico for The New York Times

The product — the latest entry in a newish category of soak-off gels — has been five years in the making by Creative Nail Design, or CND. The company mixed one-of-a-kind shades for runway models in the shows by Marc Jacobs and Jason Wu this year.