The CZ gemstone has more light dispersion (fire) and is heavier than a diamond, and although a real diamond is about 500 times harder than a Cubic Zirconia, the Cubic Zirconia is relatively hard compared to other gemstones.
There are a number of ways to distinguish the difference between a diamond and a Cubic Zirconia. The fog test is accurate and easy to perform. A real diamond cannot retain any heat, so if you breath on the stone it will fog over but with a Cubic Zirconia the warm breath will clear up immediately.
Choosing a Cubic Zirconia gemstone means you can have the luxury of a real gemstone at an affordable price. The clear and coloured Cubic Zirconia offered by George Weil have a a superior clarity which does not alter when fired with Art Clay Silver clay jewellery pieces. The CZ gems will withstand the heat from blow torch and kiln firing and will not crack or melt.