

Of all the diamond substitutes on the market, most people will be familiar with Cubic Zirconia. The peculiar gemstone has worked its way into jewelry display cases around the world over the past few decades, and for good reason. But what’s the difference between Cubic Zirconia vs diamond?
Throughout this article, we’ll discuss what Cubic Zirconia is, what it’s physical characteristics are, and how the diamond substitute stacks up against the real thing.
Table of Contents
What is Cubic Zirconia
A Short History of Cubic Zirconia
How is Cubic Zirconia Made?
What Are The Physical Properties of Cubic Zirconia?
What Makes Cubic Zirconia an Attractive Diamond Alternative?
Comparison: Cubic Zirconia vs Diamond
Closing Thoughts
What is Cubic Zirconia?
Cubic Zirconia is one of the most common diamond substitutes used in the jewelry industry. It’s a man made gemstone made out of a stabilized cubic form of Zirconium Dioxide (ZrO2). It is a clear, colorless gemstone that mimics many of the desirable properties of a diamond at only a fraction of the price.
Cubic Zirconia gemstones, commonly called CZs, were first introduced into the commercial jewelry industry in the 1970s. While it can be found in nature, it is exceptionally rare and found in very small quantities. This poor combination of traits makes using naturally grown CZs inefficient. The vast majority of the Cubic Zirconia you’ll find in a jewelry store is made in a laboratory.
A Short History of Cubic Zirconia
The first significant use of Cubic Zirconia actually wasn’t for jewelry at all. Back in the 1970s, researchers in the Soviet Union were searching for an affordable alternative to rubies for their laser experiments.
Not long after, the Soviets would perfect the art of mass-producing Cubic Zirconia and would be among the first to sell the synthetic gemstones at the commercial level. Fast forward to today, and CZs are one of the most widely used diamond substitutes on the market today.
How is Cubic Zirconia Made?
As we previously discussed, Cubic Zirconia is not naturally found in very large quantities and has to be created in a lab. And without some external help, mass use of Cubic Zirconia in jewelry simply would not be possible.
The Zirconia used in jewelry actually doesn’t start out in the cubic crystalline form. Before reaching a state where it can be used in jewelry, Zirconia in a lab is actually a powder.
In order to achieve desirable properties that are similar to diamonds, the mineral zirconia has to reach its cubic form. To do this, the powdered mineral has to be heated to nearly 5000℉. As it’s heated, Cubic Zirconia crystals begin to form. However, Zirconia is not stable at such a high temperature and cannot maintain the cubic crystal structure on its own.
Stabilizing compounds like yttria or calcium are added to stabilize the mineral once it reaches cubic form. Then the Cubic Zirconia is ready to be cut and be made into jewelry.
What Are The Physical Properties of Cubic Zirconia?
When comparing Cubic Zirconia vs diamonds, this is what people really want to know. What makes diamonds so much more expensive than CZ? How different could they possibly be?
There are three categories to consider when comparing the two.
Brilliance
One of the defining features of a diamond is its brilliance. That sparkle you see when you’re browsing your local jewelry store. Without its brilliance, a diamond would be far less appealing in any aesthetic setting.
In order for a gemstone to be a good diamond alternative, it needs to also display a level of brilliance. Otherwise, it’s just a cheap, colorless rock.
While CZs don’t achieve quite the same level of brilliance as a diamond, they do have a shine all of their own. When you shine a direct light on a diamond, it reflects a lot of white light back at your eyes, giving it that signature white glow. This is caused by its high refractive index.
On the other hand, Cubic Zirconia has a lower refractive index. So instead of the brilliant white light that you would get from a diamond, CZs emit more of a rainbow-colored light.
Hardness/Durability
Another defining characteristic of a diamond is its level of hardness and durability. Diamond is the hardest naturally occurring mineral. On the Moh’s Scale, which ranks a mineral’s scratch resistance, diamonds score a perfect 10. But do keep in mind that diamonds are not impervious to being scratched, but it should be much more difficult with regular wear.
While not nearly as tough as diamond, Cubic Zirconia scores an 8.5 on the Moh’s Scale, making it tougher than garnet, amethyst, and even reinforced steel.
So, you will have to regularly take care of your CZ jewelry, and you should take note that it will not keep its brilliance anywhere near as long as a diamond. With regular wear, your CZ jewelry should last around two or three years before it becomes noticeably tarnished.
Color & Imperfections
Another noteworthy feature of Cubic Zirconia is its color. Or rather, its lack thereof.
Naturally occurring gemstones will have imperfections. This is simply because nature is not a controlled environment and flawless development is hard to achieve. Some of these imperfections can cause gemstones, especially diamonds, to have an off-color or variant hue. For diamonds, this is usually a yellow or even brown tint.
Since CZs are made in a controlled environment, they’re far less likely to have the same imperfections as naturally occurring gemstones. This makes them practically colorless.
What Makes Cubic Zirconia an Attractive Diamond Alternative?
Hopefully, up to this point, it has become pretty clear that there are some significant differences between the two stones. You may be wondering why CZs are even a part of the discussion if they’re just an imitation of genuine diamonds. There are three reasons that some might consider choosing Cubic Zirconia vs diamond when at the jewelry store.
Lower Cost
This is hands down the number one reason most people will consider buying jewelry made with CZs or other faux diamonds. Given the diamonds have to be extracted from mines, are desired all around the world, and exist in a limited supply, it shouldn’t be a surprise that they’re far more expensive than their lab-made counterparts.
A 1-carat diamond can cost anywhere from $1800 into the $10,000+ range, depending on its grading.
A 1-carat Cubic Zirconia stone will only cost around $20.
Therefore, if budget is a major factor in your decision-making process, then Cubic Zirconia is likely a good alternative for everyday jewelry.
Fewer Ethical Issues
Outside of cost, ethical concerns have plagued the diamond industry for the past three decades. Even after processes were put in place in an effort to keep “blood diamonds” from hitting the consumer markets, there are other ethical concerns that continue to plague the minds of consumers.
As ethical sourcing of consumer goods becomes a larger issue, many will probably take issue with the low wages, poor working conditions, and other human rights issues occurring in some mining outfits. While there are certainly ways to find ethically sourced diamonds, lab made alternatives may be a more attractive option.
Since CZs aren’t mined, those ethical issues aren’t a problem for conscious consumers.
More Environmentally Friendly
While this is technically still an ethical concern, I think it deserves its own mention. One of the largest issues facing the diamond market is the havoc that unregulated mining operations can wreak on the environment.
If environmental protection laws aren’t strict in countries mining diamonds, then deforestation, soil degradation, and ecosystem destruction can become major issues.
That being said, countries like Canada have taken great steps to ensure that diamond mining isn’t harmful to the environment.
And, of course, since CZs aren’t mined like traditional gemstones, this becomes a non-issue during the shopping experience.
Comparison: Cubic Zirconia vs Diamond
Outside of the few downsides that we discussed above, diamonds really come on top in every category. For the average person, the cost is really going to be the most important factor when choosing between an authentic diamond and an imitation.
Brilliance
Diamonds have a higher refractive index of around 2.42, whereas a CZ has a refractive index of around 2.16. Diamonds also have a lower light dispersion rate at 0.44, while CZ is around 0.60.
The lower dispersion means that a diamond will have more of a white glow when hit by direct light. This contrasts the CZ stone, which will have a more colorful, “rainbow-esque” glow to it.
These two factors make it easy to differentiate between the two. When you’re comparing Cubic Zirconia vs diamond, diamond is the clear winner.
Hardness and Durability
Diamonds are the hardest naturally occurring minerals. It’s incredibly durable, and a quality piece of diamond jewelry can be passed down through the generations.
While a Cubic Zirconia stone isn’t a slouch at 8.5 on the Moh’s scale. Despite their hardness rating, CZs are nowhere near as durable as diamonds and won’t remain untarnished for more than a couple of years.
Clarity and Color
These are two areas where CZs actually excel. Since natural crystals will have imperfections, diamonds are more likely to have a yellow or even brown tinted color.
This is an issue CZs don’t face since they’re made in a lab. They’ll be completely colorless and should be completely clear when you buy them. Of course, that clarity can be diluted as the CZ is exposed to the elements.
However, it should be noted that the clarity and color can make CZs look fake because they’re too perfect looking.
If budget is more of a concern, then Cubic Zirconia is a very suitable alternative to diamond for everyday jewelry. But if you’re shopping for an engagement ring or wedding band, then there is no substitute for the real thing.
Once you take out the lower price point, Cubic Zirconia is outclassed by diamonds on every level.
Whether you’re looking for fashion jewelry to wear on your next night out, or you’re looking to propose to the love of your life, LeoDaniels can help you find the perfect piece.
Schedule an appointment today to speak with our jewelry concierge team!