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What are CZ Stones?

CZ stones, sometimes called cubic zirconia, are artificially reproduced gemstones that closely resemble diamonds. Cubic zirconia should not be confused with Zircon which is a naturally occurring gemstone. CZ stones are used for inexpensive jewelry and as a component in the manufacture of lasers.

Although CZ stones commonly are colorless like diamonds, color can be added to them to simulate other gems. The addition of metal oxides, such as cerium oxide and copper oxide during manufacture, produces simulated gems with color.

History
- The Russians used CZ stones in lasers as an alternative to natural rubies.
  
  The CZ stones used in jewelry are artificially reproduced forms of a naturally occurring mineral. Naturally occurring cubic zirconia is an oxide of the mineral zirconium. Baddeleyite, a naturally occurring zirconium oxide was discovered in 1892.
  
  In the 1970s, Soviet scientists developed a microwave process for creating simulated gemstones using zirconium dioxide and yttrium. Cubic zirconia made in this manner was developed for use in laser technology due to a lack of natural rubies in the USSR.
  
  CZ stones produced using this process are flawless and diamond-like in appearance. That, added to the fact that CZ stones are inexpensive to produce, makes them the most economically important simulated gemstones on the market, according to Man Made Diamond Information.
Simulated vs. Synthetic
- CZ can be colored by adding metal oxides to the zirconium oxide powder.
  
  CZ stones are not synthetic gemstones. Synthetic gemstones are grown in a laboratory and have the same chemical and physical characteristics as their naturally mined counterparts. They are produced in a lab by reproducing the natural conditions under which their natural counterparts are formed.
  
  Simulated gemstones, such as cubic zirconium do not have the same characteristics as the natural gemstones they simulate. Cubic zirconia is one of the most successful gem stimulants due to its hardness and clarity. Other diamond stimulants can be made using colored glass or silicon carbide.
Zirconium Dioxide
- Oxides of Zirconium are used in CZ stones and ceramics.
  
  CZ stones are the cubic crystalline form of zirconium dioxide. The metal oxide, zirconium dioxide is the second most commonly found form of zirconium. This heavy metal oxide is commonly used in the manufacture of ceramics and simulated diamonds.
  
  Zirconium is the oldest mineral that can be found on the earth and is more common than chlorine or copper. The element has extremely low chemical reactivity, is very hard and possesses an exceptionally high melting point, according to Da Na Knowledge Base. These properties, its resistance to acids and the fact that it is nonmagnetic make zirconium dioxide useful for the manufacture of ceramics and as a thermal barrier coating material in jet engines.
Skull Melting
- The extremely high melting point of zirconium dioxide makes it very difficult to work with because no crucible can withstand the temperatures needed to melt it. CZ stones are manufactured in an ingenious way --- they are made in a microwave.
  
  Cubic zirconia stones are grown in a process called a skull melt. In skull melting, the zirconium dioxide powder actually makes its own crucible. A mixture of zirconium dioxide doped with calcium or yttrium added as a stabilizer is placed inside a microwave furnace. The zirconium dioxide powder is surrounded by copper tubing filled with water to keep the exterior of the powder cool as the interior is melted using microwaves.

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