Moissanite, lab-grown diamonds and natural diamonds are the three most popular choices for engagement rings, and the key difference is what they're made of and where they come from. Moissanite is a lab-made silicon carbide gem with more fire than diamond. A lab-grown diamond is a real diamond, chemically identical to a natural one, grown in weeks. A natural diamond formed deep in the earth billions of years ago. Below, we'll cover the history, pros and cons of each, and their differences and similarities may surprise you!
Moissanite vs. Lab Diamond vs. Natural Diamond at a Glance
| Moissanite | Lab-Grown Diamond | Natural Diamond | |
|---|---|---|---|
| What it is | Silicon carbide, made in a lab | Real diamond (pure carbon), grown in a lab | Real diamond (pure carbon), formed in the earth |
| Hardness (Mohs) | 9.25 | 10 | 10 |
| Sparkle | Strong rainbow fire, a "disco ball" look | Classic diamond brilliance | Classic diamond brilliance |
| Grading report | Usually the maker's own certificate | Graded by major labs such as IGI | Graded by major labs such as GIA |
| Price | Lowest of the three | Low to Mid-range | Highest of the three |
| Resale value | Little to none | Little to none | Holds the most value of the three |
What Is Moissanite?
Photo: Gems of Science
Moissanite is a gemstone made of silicon carbide, and virtually all moissanite sold today is grown in a lab. It's a relatively new discovery in the gem world: Henri Moissan first found it in 1893 in samples from a meteorite crater in Arizona. Natural moissanite is incredibly rare, so the stones on the market are lab grown, replicating its chemical composition exactly, but large, eye clean and even in different colors.
Moissanite is a 9.25 on the Mohs hardness scale, second only to diamond among popular gemstones. Its dispersion, the way a stone splits light into rainbow colors, is more than double that of diamond, which gives moissanite noticeably more colorful flashes, or "fire." This, alongside its commonly icy-white appearance, is what makes moissanite a growing interest in the bridal industry. Moissanite is also the most affordable of these three options, costing even less than lab-grown diamonds.
Moissanite does come with some potential drawbacks. Its famous "disco ball" level of fire can look unnatural or overdone to some, especially compared with the more subtle brilliance of a diamond. While moissanite is usually clean to the naked eye and colorless, major gem laboratories don't issue grading reports for it, and it usually comes with the maker's own certificate instead, so details like clarity and color aren't independently verified. Finally, some stones can show undertones of yellow, green or gray in certain lighting.
What Is a Natural Diamond?
Photo: GIA
A natural diamond is pure carbon that formed deep in the earth billions of years ago, and it's the hardest naturally occurring mineral on earth. The icon with centuries of history, the natural diamond was first discovered in India, and today it's mined around the world. Diamonds come in many colors, each with its own rarity, with colorless being the most popular. Trace impurities, such as nitrogen, can affect a diamond's color.
Earth-mined diamonds hold their value the most of the three options here, though they rarely resell for close to their retail price. Thanks to their long history, we understand them best and have many reputable laboratories to grade their quality, helping consumers make educated decisions (see our guide to how to read a diamond grading report). That long history has also taught us how to cut diamonds to sparkle their best, through hundreds of years of trial and error. Natural diamonds also have sentimental appeal for those who love the history behind the stone and its journey from the earth to the ring.
A natural diamond does come with potential downsides, the most prominent being its potentially prohibitive cost. Natural rarity and controlled supply make earth-mined diamonds by far the most expensive of these options. Since they formed naturally, they also come with their own quirks that some may love or hate, from inclusions to variations in color. Some people also have ethical concerns about mined diamonds, including their impact on the environment and human rights. Many initiatives have been created to address this, from the Kimberley Process, an international certification scheme for rough diamonds, to CanadaMark diamonds.
What Is a Lab-Grown Diamond?
Photo: GIA
A lab-grown diamond is a real diamond, chemically and physically identical to a natural diamond, but grown in a laboratory in a matter of weeks instead of forming in the earth. A newcomer to the jewelry industry, lab-grown diamonds have taken bridal by storm. The first diamonds were grown in a lab in the 1950s, and the first gem-quality lab diamonds were produced around 1970, but they only became commercially practical for jewelry in the 2000s and 2010s. Their recent growth has been dramatic: according to The Knot's 2026 Real Weddings Study, 61% of engagement rings bought in 2025 featured a lab-grown center stone.
Lab-grown diamonds are chemically identical to natural diamonds, and many, especially those grown by the CVD method, are Type IIa: an exceptionally pure type of diamond, with fewer impurities, that makes up less than 2% of natural diamonds. Lab diamonds are grown in two ways, CVD (chemical vapor deposition) and HPHT (high pressure, high temperature), and they're relatively quick to create in colorless shades and large carat weights, something that takes the earth billions of years. Because they're mass produced around the world and have flooded the market quickly, they're far more affordable, making them approachable for many people who may not otherwise have been able to afford the diamond they dreamed of.
Putting aside the debates between fans of natural and lab diamonds, there are some potential downsides to lab-grown diamonds. Growing diamonds is not yet an exact science, and most fancy-color lab diamonds get their color from treatment after growing, so finding a specific natural-looking color or hue can be harder than finding a white diamond. Their rapid rise in recent years has also raised questions about energy use and working conditions in growing and cutting. Additionally, due to mass production, lab-grown diamonds typically have little to no resale value.
Still Undecided? We Can Help
Deciding which stone is right for you can be difficult, and we're here to help, whether that means sourcing your perfect stone or even custom growing and cutting it. Visit our engagement ring collection and our bespoke page below for inspiration, and reach out anytime. We'll be happy to help with your project at Shahla Karimi!
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