Cubic zirconia is a hard stone but not as tough as moissanite. This means that moissanite is over 3 times more resistant to breaking or chipping than CZ making it a far more superior material for anyone looking to wear it daily as a diamond alternative. Moissanite stones don't lose their shine or become clouded or gloomy over time. While a diamond is harder than a moissanite ring, both of these stones have similar durability. In fact, they're second only to a diamond on the Mohs scale, which makes them harder than any other gemstone out there.