Great Question!
SHORT VERSION:
The differences to the eye can be hard to perceive, but here is a SHORT VERSION of some interesting differences of cubic zirconia and diamond.
The main difference is possibly the way they are "cooked", or processed. A second major difference is the atomic and chemical structures. They are not the same.
Zro2,or zirconia, is not found in nature as a pure oxide, but is found in Zircon, or Zrsio. Zirconia is processed out of Zircon. Cubic zirconias are a chemical phase form resulting from heat applications to the Zircon. By melting Zircon and cooling, gemstones can be produced which simulate diamond, ruby, topaz, and emerald. These materials are also known a cubic zirconias and are synthetic gems. Zirconia are used in electronic application, othopaedic implants, and refractorty applications. There are alot of industrial uses for both diamonds and zirconia.
A DIAMOND IS FOREVER!!
A diamond is a carbon and is made in the earth's mantle carbonate fluids at temperatures and pressures much higher than man made ones. Carbon atoms in diamonds also come from outerspace and every atom of carbon in a diamond was born in a star.
Diamonds found in space meterorites can measure hundreds the times of concentrations found in the richest diamond mines on Earth. There is a hardness difference that results from the atomic structure of the carbon in diamond. The diamond atoms can not move around easily in the molecular structure due to it's grid shape. Earth thermal and pressure processes helped short chemical bonds develop. Diamonds also occur in fancy colors. The most valued are large, clear and refractive.
The difference is metaphorically like an expensive piece of Waterford Crystal and a K-mart glass clear plate. Both are glass. One can be carved and molded better due to heat and chemical processes used to make glass from quartz or silicas.
One breaks easier and one is alot more expensive.

From teacher - November 26, 2004 at 09:26:06
Email: lkeller[ ]lexington.k12.mo.us

Message: 35018