Natural Diamond vs Cubic Zirconia: Comparison and Guide

Last Updated on June 16, 2023 by Juli "Jewels" Church

Curious as to how natural diamonds and cubic zirconia match up against each other? You're in the right place!

In this Learning Guide, I'll tackle everything you need to know about these two stones as well as answer these popular questions:

natural diamond vs cubic zirconia

Images via Wikimedia Commons

  • Are there natural cubic zirconia stones?
  • Is cubic zirconia and zircon the same thing?
  • Why don’t diamonds sparkle as much as cubic zirconia?

Diamond vs Cubic Zirconia: Origin

Diamonds and cubic zirconia are both colorless stones, but they have very different origins. Let's see how these two gemstones compare.


Natural diamonds start out as pieces of pure carbon atoms that have been subjected to extreme heat and high pressure deep within the earth. The conditions in the earth cause the carbon to become a diamond crystal. The crystals form and are carried up through the surface due to volcanic eruptions.

"Rough Diamond" credited the justified sinner

"Faceted Diamond" credited James St. John

Natural diamonds may occur as colorless diamonds or fancy colored diamonds. The locations for natural color diamonds are different than the places listed below.

Diamonds can be found in a number of places including but not limited to:

  • Russia
  • Botswana
  • Canada
  • Australia
  • Republic of Congo
  • United States

2 Carat 14K White Gold Natural Diamond Tennis Bracelet from Blue Nile

Cubic Zirconia

Once upon a time, there used to be natural cubic zirconia, but you should expect all cubic zirconia on the market today to be manmade. Natural cubic zirconia is extremely rare.

Cubic zirconia is the product of powdered form of zirconium oxide melted with calcium and magnesium. It is known as the cubic crystalline form of zirconium dioxide. Scientists have been able to extract zirconium oxide from the mineral baddeleyite in order to synthesize cubic zirconium.

Unlike a real diamond, cubic zirconia doesn't contain any carbon at all.

Faceted Cubic Zirconia stone credited maicos 

Up close CZ stone credited Kurayba

By heating it up past 4000˚F, scientists are able to produce flawless cubic zirconia. Though the process of creating cubic zirconia stones is pretty easy, different companies produce it different ways. CZ stones can be colorless or any color of the rainbow.

Cubic zirconia is often used for costume jewelry, rhinestone jewelry or clothing detail, and nail art. It is best known as a diamond simulant. You may see cubic zirconia referred to as an number of different names on the web such as:

Diamond vs Cubic Zirconia: Appearance

Many people will take a look at cubic zirconia vs diamonds and think they're basically the same because they're colorless. But when you look closely, at both their appearance and chemical composition, you'd see they are very different.


You've probably heard the sparkle of a diamond is comparable to none. They're not wrong. Technically there's no stone that sparkles like a diamond. Diamonds have a subtle brilliance in natural light. There's a delicate balance of white light and rainbow light that complements each other.

Diamond brilliance can also be known as a diamond's fire. The diamond's fire the result of the light dispersion. Diamonds have a dispersion rate of 0.044. Gemstone light dispersion isn't often seen, otherwise it would generate the rainbow effect like moissanite and cubic zirconia.

Synthetics and Imitations

Synthetic diamonds are a big jewelry trend that's here to stay. They're the ethical alternative to conflict-free diamonds and have all the same qualities as a natural diamond. Lab grown diamonds are real diamonds. Synthetic stones are not imitations. They are lab created, but they have the same properties as natural gemstone fine jewelry.

Colored diamonds and colorless diamonds can both be lab-created. The main difference between them is that lab grown diamonds cost much less than natural diamonds of the same quality.

Cubic Zirconia

Cubic zirconia gives off more colorful light than a diamond engagement ring. That's because cubic zirconia possess excess light dispersion at a rate of 0.060. When looking at a diamond and a cubic zirconia from a distance, you'll notice the rainbow light over the white light.

Though cubic zirconia has excessive light dispersion when compared to diamonds, it has a much lower refractive index. The refractive index of gemstone lets us know how much light bends and reflects back out of the stone to our eyes. Both refractive index and light dispersion are one of biggest ways to distinguish diamonds and gemstones from another gem or a fake stone.

Cubic zirconia stones may also be treated by coatings in order to protect it from scratching. These coatings can and will fade over time.

Synthetics and Imitations

Cubic zirconia is cheap and already man-made, so there's need for fakes. However, cubic zirconia is the go-to diamond fake or diamond simulant. Cubic zirconia also is often compared with Swarovski crystals. Swarovski crystals have had a better public relations team than cubic zirconia as they are pretty popular. They're also cheaper and easier to make then cubic zirconia, if you thought that possible.

Swarovski Crystal Studs credited Mannia&Titta

Diamond vs Cubic Zirconia Stones: Price

If you were to compare a flawless diamond with a flawless cubic zirconia stone's price tag, they'd be extremely different.

Scientists are able to produce flawless cz stones cheaply and in abundance. The ingredients are readily available to produce a cz stone, so there's no rarity or value in it. That being said, the price of cz stones can range from as little as $5 to over $100, depending on quality and carat weight.

Doesn't make sense, does it?

Though the process to produce cubic zirconia is easy, there's multiple ways to do it. Not every company that produces cubic zirconia does it the same way. Because of this, not all cubic zirconia stones are created equal. They aren't all priced the same either.

14K Yellow Gold Children's Earring Cubic Zirconia from Helzberg Jewelers

You really take the risk of getting a bad cz stone if you just pick any old seller, like on Amazon. There's a lot of cubic zirconia cheaply made, but no real way to tell until it's too late.

Diamond vs Cubic Zirconia Stones: Value

If the price of a cubic zirconia engagement ring isn't high, you can imagine the value isn't high either. There's no resale value or market cubic zirconia worth. It's easily available. The most monetary value you could get from a cubic zirconia ring will be in a solid sterling silver or gold ring setting.

You'd expect that with the price tag of an eye clean diamond (without natural imperfections to the naked eye) , it'd be worth just as much or maybe just a little bit less.

Hardly. Colorless diamonds aren't worth investing in. Sure, you can sell it to someone on Facebook Marketplace. But pure monetary value of your mined diamond for selling back to diamond jewelry stores or pawn shops is maybe a 1/3 of what you paid.

Unless your natural diamond engagement ring is a high carat weight and flawless, it's not worth the resell in my opinion. It's also the opinion of many jewelry lovers like myself that it's not about the monetary worth, but the sentiment. But if you really wanted to invest in diamonds, the value is in a fancy color diamond because of its rarity. They are highly expensive.

Lab created diamonds have even less value. Many popular online retailers like James Allen and Blue Nile offer trade-ins/trade-ups for their mined diamonds, but not for their lab created diamonds. The prices of synthetic diamonds fluctuate, so stores would lose money taking lab grown engagement rings back. But you can always a lab grown diamond on marketplace sites if need be.

Value Over Time

It's true, you shouldn't let the monetary value of a stone deter you from choosing it as the center stone of your engagement ring. But it is important to choose a gemstone that can hold up over the years of your marriage. The majority of people plan to wear engagement rings and wedding rings for years and years.

Gemstones and the natural metals they're set in are natural products. They don't last forever, no matter how good the craftsmanship is. Certain gemstones don't make good center stones for everyday wear because of dirt and dust particles in the air.

That's not to say that you can't wear them, but they will become scratched over the time. The Mohs hardness scale tells us how well a mineral can stand up to dust in the air. It doesn't translate to how durable it is, but how scratchable. It's only one of the elements in gemstone wearability.


Image by the National Park Service. Public Domain.

Mined diamonds and lab made diamonds are hardest naturally occurring mineral on the Mohs scale. As far as dust in the air goes, they're perfect for daily wear. They can chip, crack, or break if struck hard enough. However, most transparent faceted gems are capable of doing so.

Cubic zirconias reach a 8-8.5 on the Mohs scale. While 8 isn't far from 10, the hardness levels don't quite work that way. A cubic zirconia will hold up for a while, as long as it's well cared for. But diamonds will hold up longer and with less care than cubic zirconia.

Natural, lab created diamonds, and cubic zirconia are all considered brittle, meaning they can crack if hit hard enough. Cubic zirconia usually has thin edges which can make it susceptible to fracturing.

Don't be surprised if you end up with a cloudy CZ stone. Dust, dirt, and mineral residue will cause it to wear down. Some of the damage is irreversible. Fortunately cubic zirconium is easily affordable.

CZ engagement rings don't stand up to heat well, so it's important to keep your ring out of any extreme temps, like while cooking or being out in prolonged sunlight.


So while diamonds and cubic zirconia may be clear colored stones, there's much more to them than what lies on the surface. Their tenacity, scratchability, and the way they return light to our eyes is much different. So is their price, value, and longevity.

These two stones really are polar opposites, but both can have a place in your jewelry collection. For inexpensive jewelry, I recommend cubic zirconia. But if you want lasting quality for an engagement ring, a diamond will be worth the extra cost in the end.

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