What is Moissanite? The Ultimate Guide to the Diamond Alternative

Stdiam Premium Moissanite Jewelry- Stdiam

Learn how moissanite and diamond compare in appearance, durability, and price to select the ideal gemstone for you.

Expertise you can trust: Stdiam is known for its award-winning jewelry designs and seamless, innovative shopping experience. This Stdiam gemstone guide compares moissanite vs. diamond, showcasing their differences in appearance, durability, price, and more. All Stdiam guides are meticulously researched and reviewed by our certified gemologists, content, editorial, and brand teams before publication to ensure industry-leading excellence and accuracy.

Moissanite is a gemstone composed of silicon carbide, often called the “gemstone from the stars.” It was discovered in 1893 inside a meteorite in Arizona by Nobel Prize–winning chemist Henri Moissan, who later identified it as silicon carbide and gave it its name.

Naturally occurring moissanite is extremely rare. Today, it is grown in laboratories using advanced technology in controlled environments. Lab-grown moissanite is traceable, requires no mining, and has a significantly lower environmental impact than mined gemstones.

Now widely used in fine jewelry, moissanite has become a popular alternative to diamonds, especially as a center stone in rings.

No, a moissanite is not a diamond. Professionals grow them in laboratories because they are visually similar to diamonds, but compositionally they’re quite different. Diamonds are composed of carbon and moissanites are composed of silicon carbide.

While the untrained eye may visually perceive a moissanite as similar to a diamond, it has a higher refractive index — meaning it produces more rainbow ‘fire’ than a diamond when light hits the stone’s surface. Diamond is also physically harder than moissanite, which is a 9.25 on the Mohs hardness scale compared to a diamond’s rating of 10.

While they both feature dispersion, scintillation, and are both considered to be good thermal conductors, moissanites and diamonds are otherwise distinct.

If you are not trained in the differences between diamond and moissanite, telling the difference can be difficult. The best way to tell the difference is to line up two similarly sized gemstones, one moissanite, and one diamond, and compare them next to one another.

To officially confirm the difference between a moissanite and a diamond, take it to a trained professional. By examining the ‘doubling’ of opposing facet junctions with a loupe, they can validate if your stone is a moissanite or a diamond.

Key Feature	Stdiam Moissanite	Natural Diamond	Lab Diamond
🛡️ DURABILITY (Mohs Scale)	9.25	10	10
💎 BRILLIANCE (Refractive Index)	2.65 - 2.69	2.42	2.42
✨ COLOR (Presence)	D - Colorless	D - Z Varies	D - F Range
🏷️ PRICE (Value)	Exceptional Value	High Premium	Medium
🌍 SOURCING (Origin)	Ethical Lab	Mined	Ethical Lab