Moissanite vs. Cubic Zirconia (CZ)

If you search on the internet today, you will find dozens of different companies each trying to market their own alternative to diamonds. To be able to cut through all of the mistruths and confusion that is created by these marketing efforts, one has to understand the top myth currently out there:

If the seller does not clearly identify what their diamond simulant is, you can very safely assume it is a form of CZ. There are certainly differences in quality and appearance of CZ, and the cutting/polishing will affect final appearance. However, unless the seller can provide some actual proof concerning their claims, you can safely and correctly assume it is CZ.

Two man-made diamond alternatives currently exist in the market: CZ and Moissanite. There are other stones that are used as substitutes such as white sapphire, white topaz, etc. but they are not nearly as brilliant.

Many people reading this article might be initially perplexed by this statement: "What about Diamond Nexus, Russian Brilliants, Carat, etc.?" The cold hard truth is that all of these companies sell CZ or Cubic Zirconium. Some simply avoid naming their simulant (Russian Brilliants), others take an honest approach and explain that they are CZ (Carat.cc), while other take a less than honest approach, attaching unsubstantiated claims to their CZ stones and denying that it is even CZ when asked point blank by a customer (i.e. Diamond Nexus, learn more about Diamond Nexus claims here).

In his article, "Synthetic moissanite: A new man-made jewel", Kurt Nassau, Ph.D. Bell Laboratories, NJ and member of the Board of Governors of the Gemological Institute of America (GIA), stated that Moissanite "provides a believable diamond substitute that is closer in appearance and heft to diamond than any other gemstone material." Moissanite's "properties are overall closer to those of diamond than any other simulant."

The ability of a gemstone to withstand every day wear is an important consideration, and for many women it is the most important. Part of the allure of a diamond is that they are millions of years old. Therefore they have withstood the test of time. Most women who have owned a piece of CZ jewelry note that although beautiful when brand new with everyday wear and tear the CZ soon became dead and lifeless. It is a stone with a finite lifetime.

So what about Moissanite? Moissanite is extremely hard, much harder than CZ, sapphire and rubies. Moissanite gemstones are FOREVER BRILLIANT and will be just as beautiful generations from now as the day you buy it.

There are two principal ways to measure the durability of a stone: its resistance to scratching (hardness) and its resistance to breaking / chipping (toughness).

Moissanite is more than two times as hard (resistant to scratching) as a Cubic Zirconium (CZ) and more than three times as tough (resistant to chipping/breaking).

Click here to read more and see the source data.

There are several inherent problems with CZ that do not exist in Moissanite or Diamonds:

#1. CZ is an unstable compound at room temperature and it naturally wants to change its molecular form. For that reason another molecule is introduced to the crystal called a "dopant". This dopant functions as a doorstop and prevents this chemical transformation from taking place. Yttrium, for example, is a very common dopant. But this "doorstop" can break down, and when it does, the CZ will begin transforming, changing color and losing much of its optical properties.

Moissanite is guaranteed to never change color. This guarantee isn't just a promise to replace the stone if it changes color, it is a guarantee it will not change color!

We have been selling Moissanite for many years, and our customers have never had a single stone change color. Our distributors have reported the same experience to us. Part of the reason Charles & Colvard addresses this directly in the warranty is because it is such a common problem with CZ stones.

#2. Another instability problem with CZ is that it can, and will, chemically react with oxygen, becoming cloudy in appearance.

Moissanite is guaranteed to never cloud. Again, this guarantee isn't just a promise to replace the stone if it clouds, it is a guarantee it will not chemically react with the atmosphere and cloud.

Part of the reason Charles & Colvard addresses this issue directly in the warranty is because it is such a common problem with CZ stones.

#3. CZ is sensitive to heat. When exposed to too much heat, CZ stones will shatter and turn a very opaque, milky color. This is not a problem when it comes to everyday wear, but can be a problem if you would like to make modifications to your jewelry. For this reason, many jewelers will refuse to perform repairs on CZ jewelry.

For example; sizing a ring can be an issue if the CZ stones are too close to the bottom of the band where the sizing is performed. When the band is soldered back together, if the CZ stones become too hot, they will shatter, requiring the jeweler to inspect, remove and replace any broken CZ stones. Other modifications such as changing the head (prongs) to accommodate a larger stone or soldering two CZ rings together are simply not possible without damaging some or all of the CZ stones in question. Another common repair is re-tipping or replacing a broken prong. With Moissanite or Diamond the jeweler can rebuild the prong on top of the stone. With CZ, the jeweler has to completely remove the stone before repairing the prong, and risk damaging more prongs in the process.

Moissanite does not have the same heat sensitivities. In fact, Moissanite is so stable that it is more heat resistant than a diamond. All of the repairs mentioned and others that were not mentioned are safe as Moissanite can "take the heat" so to speak.

Porosity: CZ is a somewhat porous material, or in other words, it has tiny microscopic holes. With time hand oils, lotion, etc. will seep into the stone and cause the stone to cloud, change colors, and become lifeless in appearance. (Diamond Nexus' newest claim is their stone is not porous. However in light of the fact that it is proven to be an ordinary CZ crystal, this claim is likely to be untrue as it is made without any corroborating evidence). See our Diamond Nexus info page for more info on the Nexus CZ.

Affinity to Dirt: CZ has a very high affinity for dirt, grime, hand oils, etc. and requires constant cleaning to maintain its brilliance, typically much, much more than Moissanite and diamonds. Women who regularly wear CZ have reported that it becomes nearly a daily cleaning ritual to make their CZ sparkle. Because of Moissanite's carbon-based composition (SiC), Moissanite's affinity for dirt and oil is much lower than that of a CZ and similar to that of a diamond. Moreover, because of the high brilliance and fire of Moissanite, it will still sparkle even when dirty (although cleaning is recommended).

The beauty and "sparkle" of natural diamonds is found in the brilliance, fire, and luster of the gemstone.

Brilliance is the amount of white light that a jewel reflects back to the eye. Moissanite has nearly 25% more brilliance than CZ (CZ has 10% less brilliance than natural diamonds).

Fire is the amount of colored light that a jewel reflects back to the eye. Moissanite has nearly 58% more brilliance than CZ.

Luster is a description of the way light interacts with the surface of a crystal. The higher the luster, the greater the amount of light reflected from the surface of the gemstone. Luster is measured using the refractive index of the stone. The luster of Moissanite is 50% greater than CZ (the luster of CZ is 21% lower than natural diamonds).

Click here to read more and see the source data.

"Windowing" is an optical phenomenon that occurs when light passes through a gemstone without being refracted. If windowing is present in a gemstone the observer can look through the stone as if it were a "window" or can observe large dark areas in the stone (caused by light leaking out the "window").

A well cut stone should reflect so much light that nothing is seen behind it. However this statement presumes that you are looking straight down through the top of the stone, and the stone is not tilted at all.

Tilting the stone even slightly will change the angles of light hitting the pavilion facets and may cause windowing. Each type of gem has its own range of "tilt" brilliance. The lower the refractive index the less tilting it takes to window the stone. The refractive index of CZ is substantially lower than Moissanite (1.8 - 2.17 compared to Moissanite's 2.69). The result is that although a CZ may look pretty when viewed from the top, when viewed at various angles many dark or black spots appear due to the lower R.I. This is windowing.

Although this phenomenon exists in diamonds and Moissanite, it is to a much lesser degree. Moissanite refracts and reflects much more of the light due to its superior R.I. (which is actually higher than a diamond).

For both gemologists and casual wearers of CZ, this windowing is a tell-tale sign that a CZ is a "fake". If you own a piece of jewelry set with a CZ, look at the stone from various angles. You will quickly see the windowing effect.

If you are looking for a inexpensive, fun piece of jewelry, CZ might be right for you as long as you pay a price that reflects its true value: $3 - $10/ct.

If you are looking for a unique, durable, beautiful gemstone that will be forever brilliant and fiery, we would strongly recommend giving Moissanite a try.

If you have a moment we would recommend reading one of our hundreds of testimonials left by satisfied Moissanite customers.