All About Cubic Zirconia

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Cubic Zirconia (CZ) is an inexpensive diamond alternative with many of the same qualities as a diamond. This crystalline material (or CZ) is synthetic, which means it is created in a laboratory. Due to increased demand, commercial production of CZ began in the 1970s.

Since cubic zirconia mimics a diamond but is not the same material, it is referred to as faux, fake, imitation, and stimulant. Cubic zirconia is beautiful in its own right and only becomes a problem purchase when it is misrepresented as a diamond or other gemstone.

Cubic Zirconia vs. Diamond

Despite looking similar to the naked eye, diamonds and cubic zirconia stones could not be more different. Here are some of the ways they differ:

  • A chunk of cubic zirconia is heavier than a diamond of the same size, but not as hard. CZ is rated at 8.5 on the ​Mohs scale, versus diamond (the hardest substance) at 10 and corundum (sapphire and ruby) at 9.
  • When you shop for CZ jewelry, the store will probably list a karat weight but may call it a 'diamond equivalent,' to help you understand how the (heavier) CZ would compare to a diamond of the same visual size.
  • Amazon has a large selection of fine jewelry made with cubic zirconia.
  • Cubic zirconia can be transformed into the same popular cuts and shapes that are used for diamonds and colored gemstones.
  • A white CZ is truly colorless, with none of the inclusions found in an untreated diamond—think of it as a little too perfect.
  • Cubic zirconia produces more flashes of color (fire) than a diamond.
  • Some of today's CZ is coated with a product that makes the stones more durable and lessons their fire—the stones look more like true diamonds, although a jeweler will know they are not.
  • Colorful versions of CZ are available, too, and have become popular in sync with the trend towards fancy color diamonds.

What Is the Mohs Scale?

The Mohs scale measures a mineral's durability and hardness. It's a qualitative grading system that determines the scratch-resistance of different minerals using harder, stronger minerals than the one being tested. The scale is named after German geologist and mineralogist Friedrich Mohs, who invented the grading system in 1812.

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Grades of Cubic Zirconia

Cubic zirconia can be evaluated using the same qualities that diamonds and other gemstones are graded by using the Four Cs (color, clarity, cut, and carat weight). Their grading is handled a little differently:

  • The quality of CZ's manufacturers does vary—some types are less desirable than others, and clarity is one characteristic that may differ.
  • A five-tiered system of A (lowest grade) to AAAAA (highest grade) is used to designate cubic zirconia qualities, but most retail jewelry stores (online or off) do not refer to the grades; they're often seen when purchasing wholesale cubic zirconia.
  • Ask questions and read descriptions carefully before purchasing cubic zirconia jewelry from any source.
Diamond Grading Chart
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Cubic Zirconia Suitable Engagement Rings

A CZ is not as durable as a diamond, sapphire, or ruby, and that means it is more likely to become scratched over time. If you cannot budget a diamond or other very durable gem, an engagement ring set with a cubic zirconia could be a good alternative—at least in the short term. Even if the stone gets scratched, it is inexpensive enough to replace without too much headache.

Cubic zirconia works nicely when set into necklaces, earrings, bracelets, rings, and other jewelry that is not worn on a daily basis.

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Cleaning Cubic Zirconia Jewelry

Cubic zirconia itself can be cleaned in an ultrasonic jewelry cleaner, but consider the setting materials before you drop the jewelry into the tank and turn on the switch. Use a less intense method to clean CZ jewelry crafted from sterling silver or from plated metals—dishwashing detergent and a very soft brush may be all it takes to remove the film from the CZ and return its fire.

Store cubic zirconia jewelry by itself, or well separated from gemstones that are rated as harder or softer on the Mohs scale—that type of storage is important for all jewelry to avoid scratches.

Jewelry Cleaner
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Is Cubic Zirconia the Same as Zircon?

Zircon and cubic zirconia are not the same:

  • Zircon (6 - 6.5 on the Mohs scale) is a gemstone, zirconium silicate, and is not related to cubic zirconia. Heat treated brown zircon was often made colorless with heat and used as a diamond substitute before CZ became available.
  • Zircon found in most jewelry has probably been treated with heat to improve or change its color, and some of the stones may revert to their original colors after they are exposed to light.
  • Heat treatments make zircon less durable.
  • You may see the term cubic zirconium, but that substance does not exist.
Cubic zirconium
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