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Bottom Line Recommendation: Cubic zirconia and diamonds may look similar at a distance, but differ drastically in beauty, quality and value. For a stunning engagement ring that will last a lifetime, we recommend choosing a real diamond over cubic zirconia. While you can find a cubic zirconia ring like this on Amazon for a fraction of the cost of a beautiful 3 Carat diamond ring, the diamond is a far superior option. To find a high-quality, excellently priced diamond within your budget, contact us for a complementary search and expert advice.
While the two stones carry some resemblance, cubic zirconia and diamonds differ significantly in physical structure, beauty and value. Before deciding on an engagement ring or other fine jewelry, be sure to understand the key differences. Our guide offers a full comparison of cubic zirconia vs diamonds—for everything from beauty and brilliance to cost and durability.
Cubic zirconia is a colorless, synthetic gemstone made of the cubic crystalline form of zirconium dioxide. Cubic zirconia can appear in nature within the mineral baddeleyite, although it’s extremely rare. In all cubic zirconia jewelry, the gemstones are exclusively lab-created.
Often regarded as an inexpensive diamond alternative, cubic zirconia is distinct in its aesthetic qualities and physical structure because it’s lab-grown—whereas natural diamonds are beautiful, naturally occurring gemstones.
Cubic zirconia is made by melting zirconium oxide powder with stabilizers like magnesium and calcium at 4,982ºF. After being removed from hours of heat, crystals form and stabilize. The crystals are then cut and polished. Each lab has its own specific methods for making cubic zirconia.
Cubic zirconia is significantly cheaper than diamonds. For example, a 1 Carat Round Cubic Zirconia engagement ring sells for $13.99, while a similar 1 Carat Diamond engagement ring that’s well-cut goes for $3,630. As another example, a 1.5 Carat Princess Cut cubic zirconia ring can retail for $37, whereas a 1.4 Carat Princess Cut diamond ring (with excellent Clarity, Cut and Color) costs $9,815. As Carat weight increases, the price gap only becomes larger. For instance, a 3 Carat cubic zirconia ring may sell for $190, while a 3 Carat Diamond ring with acceptable Cut, Clarity and Color is selling for $25,185 with James Allen.
From a value standpoint, cubic zirconia is worth next to nothing. If you were to try and resell a cubic zirconia engagement ring, you could perhaps retain some value for the setting. The cubic zirconia gemstone—just like other diamond simulants—carries no market value.
A diamond, on the other hand, does retain some of its market value, although we are upfront with readers that a diamond isn’t an investment. Unlike cubic zirconia, though, diamonds can also be passed down for generations as a family heirloom and keepsake. Diamonds carry a certain prestige because they are stunning, natural gemstones with a timeless appearance. Overall, a diamond’s price and value are dependent on its 4 C’s (Cut, Color, Clarity and Carat). These elements work together to form the beauty and brilliance of the stone.
While price differs significantly between diamonds and cubic zirconia, it’s essential to realize that so do the physical features, quality and beauty. In this case, a lower price does not mean a better value or deal.
The best way to tell a cubic zirconia from a diamond is to look at the stones under natural light: a diamond gives off more white light (brilliance) while a cubic zirconia gives off a noticeable rainbow of colored light (excessive light dispersion). The excess light dispersion is a key sign that the stone is not a diamond.
There are several other ways to tell the difference between diamonds and cubic zirconia, including looking at their physical, chemical and, visual properties. Knowing the differences will help you make the best decision when designing and purchasing jewelry.
The quality that most greatly affects a diamond’s beauty is its Cut—which impacts how much light reflects through the diamond’s table to your eyes. White light reflection is referred to as brilliance and colored light reflection is called fire.
Cubic zirconia contains no true brilliance or fire. It has a much lower refractive index—between 2.15 – 2.18, compared with 2.42 for diamonds. Light passes through cubic zirconia much differently—offering significantly less reflection back to the eye. By simply looking at the two gemstones under a light, you can tell the immense difference in light reflection. This stunning 0.8 Carat diamond ring, for example, will radiate more brilliance than any cubic zirconia—no matter the size.
Cubic zirconia also has a higher dispersion rate (between 0.058–0.066 compared with 0.044 of diamonds). The increased dispersion causes the CZ stone to have a “rainbow effect”—meaning it reflects too much colored light. The excess dispersion of light makes it easy to spot as a fake diamond.
Another difference between the stones is that cubic zirconia’s refractive index is 2.15–2.18, compared with a diamond’s refractive index of 2.417 – 2.419. A diamond’s refractive index is higher because light travels faster through the stone back to your eyes. A refractive index isn’t a measure that’s used to evaluate a diamond. While cubic zirconia and diamonds differ in the refractive index, it’s not a critical component to consider.
Overall, cubic zirconia is no comparison to the unmatched beauty and brilliance of a diamond.
As the hardest naturally-occurring mineral in the world, diamonds rate a perfect 10 on the Mohs scale of hardness. Diamonds are incredibly durable and resilient—making them ideal for engagement rings and everyday wear. Diamonds maintain their sparkle and beauty with minimal maintenance.
Cubic zirconia, on the other hand, ranks an 8.5 on the Mohs scale of hardness. Because it’s a synthetic material, it offers some durability. It can be worn in jewelry, but will certainly not have the longevity of a diamond. For example, cubic zirconia becomes scratched and cloudy over time.
Cubic zirconia is also slightly denser than diamonds. A jeweler or gemologist can easily distinguish a CZ stone from a diamond by weighing it on their scale. A 1 Carat Diamond Ring, like this one, will likely appear slightly larger than a 1 Carat cubic zirconia, depending on the gemstone’s shape.
Cubic zirconia can cut glass or scratch it, just like a diamond can. That’s why scraping the stone against glass isn’t a good test to see if the stone is a diamond. Both faux diamonds and real diamonds can scratch the surface. Some people used to think this was a good test, but it’s actually not a valid method.
Because cubic zirconia is made in a lab, it lacks the natural imperfections that diamonds have. A flawless diamond is incredibly rare and, thus, incredibly expensive. While some may regard cubic zirconia as flawless, they’re usually considered “too perfect” or fake-looking.
If you’re looking for a diamond, we recommend finding one that’s eye clean—meaning you can’t see blemishes and inclusions with the naked eye. Depending on the Carat weight, this generally means opting for a VS1 or VS2 Clarity grade. While you could choose a higher Clarity grade, you’ll be paying for a feature that will go unnoticed. By selecting an eye clean diamond, like this VS2 Cushion Cut, you’ll have a stone that looks practically perfect to the naked eye.
When it comes to Diamond Color, we recommend finding a diamond that appears white in relation to its setting. Based on your Diamond Shape and the type of setting, we generally recommend looking for a diamond in the G to I range, like this stunning Princess Cut halo ring. Cubic zirconia is considered colorless because it’s manufactured that way. These synthetic stones, however, often reflect an orange-tinted light, which is another clear indicator that it’s not a real diamond.
Cubic zirconia is a real, man-made gemstone. It’s a crystalline form of zirconium dioxide that’s hard and colorless. But cubic zirconia should not be considered a diamond under any scenario by both experts and non-experts. For many reasons—from chemical properties to brilliance and color—the two stones are entirely different.
Diamonds are naturally found, formed of the hardest material, and possess extraordinary beauty. Cubic zirconia is lab-created. The stones lack brilliance and lasting beauty.
Cubic zirconia and diamond are two distinct stones, even though they may look similar from afar. Cubic zirconia are synthetic, colorless gemstones that don’t offer any brilliance. Diamonds are natural, stunning gemstones found beneath the earth’s surface. When cut well, diamonds showcase tremendous brilliance and fire.
Not only does beauty and physical composition differ greatly in cubic zirconia vs. diamond, so does the value. Cubic zirconias are very inexpensive but also have no resale value. While diamonds shouldn’t be considered an investment, they maintain value over time—usually at least 50% of what you bought it for. Diamonds are highly sought after gemstones that are popular for engagement rings and other fine jewelry.
Because diamonds and cubic zirconia are unmistakably different in beauty and quality, we don’t recommend cubic zirconia jewelry. As diamond experts, we can help you find a stunning diamond at an excellent price.
Contact us today if you’d like to begin a complimentary search. We’ll walk you through everything you need to know—keeping in mind your budget and unique desires.
Here we answer the most common questions about cubic zirconia jewelry.
Cubic zirconia is a very cheap, synthetic option for jewelry, but it’s not recommended for engagement rings and fine jewelry. Cubic zirconia won’t hold up well over time, and it won’t offer nearly as much beauty as a diamond or colored gemstone.
You can get cubic zirconia wet, but repeated exposure to water will damage the stone. It’s best to take off cubic zirconia jewelry when doing water-related activities like washing dishes, bathing, and swimming. If you wear your jewelry for years doing these activities, the quality of the cubic zirconia will deteriorate. Elements in the water can impact your stone, such as chlorine, saltwater, and certain minerals.
Lab-created diamonds are not the same as cubic zirconia. Lab-created diamonds are synthetic diamonds that mirror the same physical and optical properties of natural diamonds. For instance, lab-created diamonds consist of carbon atom structures just like natural diamonds. They give off brilliance and fire just as natural diamonds do. Cubic zirconia does not carry the same properties as diamonds, and they don’t provide brilliance and fire the same way diamonds do.
Cubic zirconia lasts two to three years with everyday wear, as long as you clean and care for your jewelry. With occasional wear, cubic zirconia can last up to five years. Over time, cubic zirconia usually gets scratched and becomes cloudy.
Cubic zirconia does not rust, but the jewelry setting can. Inexpensive metals such as brass, gold-plated alloys, and sterling silver often rust over time due to exposure to oxygen in the air and water.
Cubic zirconia gets cloudy over time due to scratches, soap and mineral residue, dirt, and exposure to oxygen in the air and water. You can clean your cubic zirconia with soapy water and a soft cloth. Depending on why your gemstone is cloudy, you may not be able to restore it to its original state.
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