What Is Moissanite?

Where it comes from

In 1893 the French chemist Henri Moissan found tiny crystals in fragments of the Canyon Diablo meteorite in Arizona. At first he thought they were diamonds. They were silicon carbide, and the mineral was later named moissanite after him.

Natural moissanite is extremely rare, far too rare to be used in jewelry. Every moissanite gemstone sold today is grown in a laboratory. That means no mining, consistent quality and a much lower price than diamond.

How it looks

Well cut, colourless moissanite looks like a diamond to most people. It has a higher refractive index than diamond (about 2.65 against 2.42), so it returns a lot of light. It also has more than twice the dispersion of diamond, which shows as rainbow flashes of colour, especially in sunlight.

Moissanite is graded for colour on the same scale as diamonds. Most moissanite set in engagement rings today is colourless, in the D to F range.

How it wears

At 9.25 on the Mohs scale, moissanite is the second hardest gemstone used in jewelry, after diamond at 10. It is tough enough for an engagement ring worn every day, and it does not go cloudy over time. Clean it with warm water, mild soap and a soft brush to keep it bright.