Moissanite vs. Diamond vs. Cubic Zirconia: A Comparison Guide

Moissanite, diamond and cubic zirconia can look alike in a jewelry case. They are very different in price, hardness and how well they hold up to daily wear.

Choose the wrong one and you either pay for sparkle you cannot see, or end up with a stone that wears faster than you expected.

This guide compares moissanite vs diamond vs cubic zirconia on price, hardness, fire and durability. It also shows you how to tell the three apart and which one fits your budget.

The table below compares the three stones on the points buyers ask about most.

The takeaway: for a stone that looks like a diamond and lasts a lifetime, moissanite is the strongest value pick. For an heirloom-grade investment, diamond is unmatched. For affordable fashion jewelry that does not need to last forever, cubic zirconia is the most accessible choice.

The following section breaks down the history and origins of diamond vs moissanite vs cubic zirconia.

French chemist Henri Moissan first found natural moissanite in 1893, while studying rock samples from the Canyon Diablo meteorite site in Arizona. He first thought the crystals were diamonds. In 1904 he identified them as silicon carbide.

Natural moissanite is extremely rare on Earth. It turns up in tiny amounts in meteorites and in some rocks such as kimberlite. That is why every moissanite gem you can buy today is grown in a lab.

Gem-quality lab-grown moissanite reached the jewelry market in 1998, through a company called C3 Inc. (now Charles & Colvard) under US patent 5,723,391. Source: Wikipedia, Moissanite (checked Nov 2026).

According to the Gemological Institute of America (GIA), diamonds form deep in the earth under extreme heat and pressure. The diamond is then ejected to the earth's surface, found by force of nature or by laborers. Diamonds go through a cleaving, cutting, and polishing process.

Diamond's popularity started in India as early as the 4th century BC when diamonds were gathered from bodies of water. Soon diamonds found their way to Western Europe in the caravans traveling to Venice’s medieval markets. By the 1400s, diamonds became synonymous with Europe’s elite. India's diamond supply started declining in the 1700s. Brazil became an important diamond source dominating the market for over 150 years, discovered by pans of gold miners sifting through gravels of local rivers.

Diamonds went through many upheavals throughout the centuries as they became more available to the masses. New sources of diamonds were discovered, including in Africa, making them more widespread and available. Today, technology has allowed scientists to uncover more locations for diamonds efficiently.

Cubic zirconia is a lab-made stone. In 1937, German mineralogists M. V. Stackelberg and K. Chudoba found natural cubic zirconia, but only as microscopic grains inside another mineral. Those grains are far too small for jewelry.

Synthetic cubic zirconia was originally created for use in lasers and optical applications. Synthetic cubic zirconia's production grew over time, exceeding other earlier synthetic diamond simulants, including strontium titanate, YAG (yttrium aluminum garnet), and GGG (gadolinium gallium garnet).

Today, lab-created cubic zirconia (“cubic zirconia”) remains incredibly popular, often set into alloy metals or fine metals, utilized in both the fashion jewelry and fine jewelry category. Cubic zirconia is available in different colors, making it versatile.

For more information on cubic zirconia vs moissanite, make sure to check out our blog, Shining The Light On Cubic Zirconia Vs. Moissanite: Which Is The Better Gemstone?

Here is how the three stones differ in structure, light performance and density.

Moissanite is composed of silicon carbide (SiC), with a carbon atom surrounded by four silicon atoms in a tetrahedral form.   

Two numbers explain how a stone handles light. Refractive index shows how much the stone bends light. Dispersion, also called fire, shows how strongly it splits white light into rainbow colors.

Moissanite has a refractive index of about 2.65 to 2.97 and a dispersion of 0.104. Diamond's dispersion is 0.044, so moissanite throws more than twice as much colored fire.

Moissanite exhibits its trademark  “disco ball effect” as the stone moves with a gorgeous rainbow of color. The “doubling” of the stone can easily be seen under 10x magnification.

Moissanite has a specific gravity (“SG” density) of 3.22, making it a dense mineral. 

Diamond is known for its brilliance (the white light the stone reflects), fire (flashes of color) and scintillation (the sparkle you see as the stone moves). It has a refractive index of 2.42 and a dispersion of 0.044, with an adamantine luster.

Diamond is made up of a single element, carbon. Diamond has a cubic crystal system and an octahedral crystal habit. It has a specific gravity of 3.52, making it heavier than moissanite but not as heavy as cubic zirconia.

Cubic zirconia (abbreviated CZ) is the cubic crystal form of zirconium dioxide (ZrO2). It has a refractive index of 2.15 to 2.18 and a dispersion of 0.058 to 0.066. Its specific gravity is 5.6 to 6.0 g/cm3, so a CZ stone weighs about 1.7 times more than a diamond of the same size.

Hardness shows how well a stone resists scratches. It is measured on the Mohs scale. Moissanite rates about 9.25 to 9.5 out of 10, so it handles daily wear well.

Diamond rates a 10/10 on the Mohs scale of hardness, making it the most scratch resistant mineral on earth.

Cubic zirconia rates 8 to 8.5 on the Mohs scale. That is fine for occasional wear, but CZ is known for abrasion, which means the edges between facets wear down. Chips and dull edges show up sooner than on moissanite or diamond.

A good moissanite keeps its color. If you see a yellow or green tint, it usually comes from the stone's color grade, not from wear. Ask for the color grade before you buy. IceCartel jewelry uses D-color moissanite (see the moissanite color chart).

A stone that looks cloudy is usually dirty. Lotion, soap and skin oil build up behind the stone and dull it. A warm soapy water soak fixes this (see Maintenance and Care below).

A 1-carat natural diamond has a median price of about $4,850, and a 1-carat lab-grown diamond about $1,060 (round, G/VS2, July 2026). Moissanite and cubic zirconia cost far less. Here is how the value compares. Source: TheDiamondPrice, Natural vs Lab Diamond Price Report 2026.

Moissanite: Moissanite is significantly less expensive than a diamond, but more expensive than a cubic zirconia. Moissanite is a high-quality diamond alternative that may be accompanied by a certification for insurance purposes. Insuring your moissanite rings and pendants is a great choice. If you want something unique, check out our custom moissanite jewelry collection for bespoke designs.

• Value: Moissanite costs far less than a diamond and still holds some resale value. To see what to expect, read Moissanite Resale Value. It is also a good fit for buyers who want a lab-grown, mining-free stone.

Diamond: Diamonds are the most valuable of these three stones. They're also the traditional choice for engagement rings and other fine jewelry, known as the world's most precious stone. 

They are not as affordable as moissanite or cubic zirconia, making them investment purchases.

• Value: Diamonds suit buyers who want high-quality jewelry that holds its value over time. The cost of a diamond varies greatly with the 4Cs (carat weight, cut, clarity and color). The 4Cs are a diamond grading system. Source: GIA, Diamond Quality Factors.

Cubic Zirconia: Cubic zirconia is much less expensive in comparison to the stones of the same carat and size of diamonds and moissanite.

• Value: Cubic zirconia is an affordable option for those who love fashion-forward trends.

Cubic zirconia is cheap because it is easy to make in volume. Makers melt zirconium dioxide with a stabilizer (usually about 10% yttrium oxide) in a cold crucible and let crystals form as it cools. Source: Wikipedia, Cubic zirconia (checked Nov 2026).

It is also softer than moissanite and diamond, and most buyers treat it as fashion jewelry. That keeps the price low.

Moissanite sellers use the same D-to-Z color letters as diamond. D to F is colorless, and G to H is near colorless. Lower letters show a light yellow tint. IceCartel uses D-color moissanite. Check the moissanite color chart before you compare prices.

Cubic zirconia has no standard grading system. The 4Cs are a diamond system, so labels such as "AAAAA" on CZ are the seller's own terms. Compare size, cut and the seller's return policy instead.

Moissanite, cubic zirconia, and natural, earth-mined diamonds are all popular choices for jewelry, featuring environmental and ethical considerations. 

Moissanite and CZ are lab-created stones that do not involve any mining. Moissanite and CZ are not associated with any human rights abuses or conflicts.

Diamonds are associated with environmental and ethical concerns. Diamond mining impacts the environment, including soil erosion, deforestation, and water pollution. Additionally, there have been reports of human rights abuses in the diamond industry, including forced labor. Conflict-free diamonds are a way to absolve these concerns. However, conflict-free may not always be verified.

No, moissanite is not a diamond. Moissanite is a completely separate gemstone made of silicon carbide (SiC), while diamond is pure carbon. The two stones look similar to the naked eye because both are colorless, brilliant, and durable. But they are different minerals with different chemical compositions, refractive indexes, and prices.

The confusion comes from how moissanite is marketed. Many jewelers sell moissanite as a "moissanite diamond" because it looks like a diamond, passes most thermal diamond testers, and works in the same engagement-ring settings. Calling moissanite a "diamond" is technically incorrect. The stone is a high-quality diamond alternative, not a diamond itself. Lab-grown diamonds are real diamonds. Moissanite is not.

If you are wondering whether a stone you own is moissanite or a real diamond, the easiest test is a dual thermal-and-electrical conductivity tester. Moissanite conducts both heat and electricity; diamond only conducts heat. A dual tester will identify the difference within seconds.

No, cubic zirconia is not a diamond. Cubic zirconia (CZ) is a synthetic gemstone made of zirconium dioxide (ZrO₂), while diamond is pure carbon. CZ is the most affordable diamond simulant on the market and looks visually similar to diamond, but the two are completely different minerals. CZ is softer (8 to 8.5 on the Mohs scale vs. diamond’s 10) and has a lower refractive index, which means it does not sparkle quite the same way under light.

To anyone untrained, a CZ stone looks like a diamond at first glance. Side-by-side and under magnification, the differences become obvious, CZ has too-perfect clarity (real diamonds have natural inclusions), a slightly different sparkle pattern, and the stone will fail a standard diamond tester immediately. CZ is best understood as costume-grade jewelry: beautiful, accessible, but not built to last decades the way a diamond or moissanite is.

The quickest checks at home are weight and how the stone handles light. The only sure answer comes from a jeweler with a dual thermal-and-electrical tester.

• Look for double refraction. Under 10x magnification, the back facet edges of a moissanite look doubled. Diamond and CZ do not do this.
• Check the weight. CZ weighs about 1.7 times more than a diamond of the same size. Moissanite is a little lighter than diamond (specific gravity 3.22 vs 3.52).
• Watch the color flash. Moissanite flashes strong rainbow colors. Its dispersion (0.104) is more than twice diamond's (0.044). Diamond looks more icy white.
• Look at clarity. CZ usually looks flawless. Natural diamonds usually have tiny inclusions.
• Use a tester. A thermal tester passes both diamond and moissanite and fails CZ. A dual thermal-and-electrical tester separates diamond from moissanite.

Not sure? Ask a jeweler to test the stone. It takes seconds.

Cleaning your moissanite, diamond, and cubic zirconia jewelry every 2-3 weeks is recommended. Regularly maintaining your jewelry will remove bacteria, debris, and build-up caused by exposure from everyday cleaning products, cosmetics, and more. 

Using the warm soapy water method is the easiest way to keep your jewelry clean:

• Fill a bowl with lukewarm tap water. Mixing this solution with soap will create suds. 
•  Marie Claire online suggests using Dawn dish soap.  
• Place your moissanite ring, diamond, or cubic zirconia jewelry in the soapy water bowl, letting it soak for 10-15 minutes. This allows the build-up to loosen around the stone, its settings, and other parts. 
• Gently scrubbing with a NEW brush removes these dirt particles. 
• Please Note: using excessive force is never required–this may damage delicate design parts.
• Rinse the ring thoroughly under cool water running from the tap, removing the soapy residue. Pat dry with a soft, lint-free cloth, or let it air dry.

Tips: Removing your moissanite, diamond, and cubic zirconia jewelry before swimming in chlorine, saltwater, and bathing will keep it from damage or loss. Storing your jewelry in a box, bag, or drawer prevents loss, damage, and exposure to environmental factors.

Make sure to check out our in-depth blog, How to Clean Moissanite Ring: 7 Tips to Keep Moissanite Brilliant for more information.

Choose moissanite if you want:

• A diamond-like look for daily wear at a much lower cost
• More fire and rainbow flash than diamond
• A lab-grown stone with no mining behind it

Choose diamond if you want:

• An heirloom piece or the traditional choice for an engagement ring
• The hardest stone available (10 on the Mohs scale)

Choose cubic zirconia if you want:

• The lowest price
• Fashion jewelry you are happy to replace

When it comes to cz vs moissanite vs diamond, which is best for you? 

Moissanite is the best all-round pick for most buyers. It is hard enough for daily wear, shows more fire than diamond, and costs far less. Diamond stays the top choice for heirloom jewelry. Cubic zirconia works when price matters most and you do not mind replacing the stone.

Feel good shopping for moissanite earrings, rings, pendants and more, knowing the stone is made for years of wear.

Moissanite is a durable stone, although not as durable as diamond. Cubic zirconia is less durable, known for abrasion and chipping. 

Diamond will always remain the most sought-after precious gemstone, unparalleled in prestige and synonymous with luxury.  However, this does not mean alternatives are “less than.” Modern diamond simulants like moissanite and cubic zirconia offer endless designs in the size you want for a fraction of the cost.