It is said that it's virtually impossible to tell the difference between cubic zirconia and a genuine diamond. While it's true that it can be difficult to tell them apart with the naked eye, there are ways to distinguish between the two stones. Don't allow yourself to be fooled by an imitation diamond if you're looking for the real thing, and don't pay exorbitant prices for a diamond when there are so many visually similar cubic zirconia stones available. With just a little research into what to look for, you will be able to tell the difference between these two popular gemstones like an expert.
Even though it can be nearly impossible to differentiate between a diamond and cubic zirconia by appearance alone, a sharp eye will be able to see the subtle differences. No matter how "clear" a diamond may be graded on the D-Z color Scale, even a white-grade diamond can possess a slightly off-color tint, generally yellowish-brown. Other grades of diamonds can have a yellowish tint in various shades. A genuine diamond will have some sort of inclusion or imperfection within the stone. Both a discoloration and an inclusion will be revealed by shining a bright white light through the stone. Rather than focusing only on the appearance of the stone itself with the light illuminating it, look at the color of the light as it exits the stone and compare it to the light before it enters the stone. The color difference will be more evident here. Since cubic zirconia is man-made, they are completely colorless and flawless, indicating that they are not genuine diamonds. Also, by turning both a diamond and cubic zirconia upside down, you will see a rainbow of colors reflected from one and blue and orange flashes reflected from the other. The stone that produces the rainbow spectrum of colors is the genuine diamond. It is common for cubic zirconia to produce firey brilliance in light, especially if it contains a large number of facets. This is not the mark of a genuine diamond which, along with being firey and brilliant, also reflects a beautiful array of colors.
Most people are aware that a diamond is the hardest-known stone on earth. This is because diamonds are created naturally from carbon, giving the stone its hardness. Cubic zirconia is created in a lab using a far softer material called zirconium dioxide. For this reason, a real diamond can be identified by weight. Compare a diamond and cubic zirconia of the same carat size. The diamond will weigh more as it is the denser of the two.
Regardless of the fact that cubic zirconia is created to be flawless, colorless, and brilliant, they are almost always less costly than a real diamond. Generally, much-larger cubic zirconia will be cheaper than a significantly smaller genuine diamond. To be certain, always buy from a reputable jeweler. When purchasing from a private seller, arrange to meet at a jewelry store in order to have the stone(s) authenticated before money changes hands.
A genuine diamond will have facets with sharper edges. This will be particularly easy to see at the junctions of the facets. Cubic zirconia facets feature smoother facets with slightly rounded edges.
A genuine diamond does not perform as a thermal insulator as well as cubic zirconia. Breathe onto each stone. Your breath will disappear immediately from the diamond as it has a higher thermal conductivity than cubic zirconia.