Key Takeaways

• Moissanite has more rainbow fire; diamond has a softer, whiter sparkle.
• Both are durable enough for everyday engagement rings.
• Moissanite is sized by millimeters or diamond-equivalent weight because it is lighter.
• Moissanite offers a much bigger look for the same budget.

Moissanite and diamond are the two most popular choices for a brilliant white engagement ring. Both are beautiful, both are durable, and both can last a lifetime. The right one for you comes down to how you want your ring to look, how you live, and what you want to spend. Here is an honest comparison.

Sparkle: Brilliance and Fire

Sparkle is really two things. Brilliance is the white light a stone returns, and fire is the rainbow flashes you see as it moves.

Moissanite has a higher refractive index than diamond and more than twice its dispersion, so it shows noticeably more colorful fire, especially in sunlight. Diamond shows a slightly softer, whiter sparkle. Neither is better; they are simply different looks. Many people who love lively, colorful sparkle prefer moissanite.

Durability: Hardness and Toughness

Diamond is the hardest natural material, rating 10 on the Mohs scale. Moissanite rates 9.25, harder than sapphire, ruby and every other popular gem. In real life, both stand up very well to daily wear, and a well-made setting matters just as much as the stone.

Color and Clarity

Top-grade moissanite is graded on the same D-to-Z color scale used for diamonds. D-color moissanite looks icy white, and VVS clarity means inclusions are extremely difficult to see even under magnification.

Weight and Size

Moissanite is a little lighter than diamond, so moissanite is usually described by its size in millimeters or by its diamond-equivalent weight. For example, a 6.5 mm round is the size of a 1 carat round diamond. See our moissanite carat size chart.

Price

This is the biggest difference. A moissanite costs a small fraction of a mined diamond of the same size and look. That means you can choose a larger stone, a more detailed setting, or a matching band, and still spend far less.

Origin

Gem-quality moissanite is created in a laboratory, so no mining is involved. Mined diamonds come from the earth, and lab-grown diamonds are also available as a middle option.

Which Should You Choose?

• Choose moissanite if you want maximum sparkle, a bigger look for your budget, and a lab-created stone.
• Choose diamond if having an actual diamond is important to you and it fits your budget.

Curious how moissanite looks on the hand? Browse our engagement rings or read our FAQs.

Frequently Asked Questions

Can you tell the difference between moissanite and diamond?

Most people cannot tell with the naked eye. Some notice that moissanite shows more rainbow fire, especially in bright sunlight.

Is moissanite as durable as diamond?

Diamond is slightly harder (10 vs 9.25 on the Mohs scale), but moissanite is harder than almost every other gem and is extremely durable for everyday wear.

Is moissanite cheaper than diamond?

Yes. Moissanite costs a small fraction of the price of a mined diamond of the same size and look.