Marquise diamonds are known for their unique and elegant shape, often compared to a football or boat, with pointed ends that give them a distinct and eye-catching appearance. Originating in France, they were named after the Marquise de Pompadour, and are considered quite rare. Despite their rarity, many people may wonder how to determine whether a marquise diamond is real or not.
Here’s how you can identify a genuine marquise diamond and avoid getting tricked into purchasing a fake one.
What Makes a Marquise Diamond Unique?
The marquise diamond has an oval shape with pointed ends, and typically contains 58 facets—33 on the crown and 25 on the pavilion. Its large crown surface area can make it appear bigger than diamonds of the same carat weight, and in some cases, it exhibits a bow-tie effect. These diamonds are rare, with only 1.5% of all diamonds GIA certified being marquise diamonds.
How to Tell if Your Marquise Diamond is Real
If you want to be sure you're purchasing an authentic marquise diamond, here are some simple tests you can perform:
1. The Fog Test
Hold the diamond between your fingers and breathe gently on it. If the fog clears up immediately, it’s a real diamond. Fake diamonds, like cubic zirconia, will retain the fog for a few seconds longer.
2. The Water Test
Place a loose marquise diamond into a glass of water. If it sinks to the bottom and stays there, it’s a real diamond. Fake diamonds are less dense and may float or hover just beneath the surface.
3. The Read-Through Test
Place the loose diamond on a piece of text and look through it. A real diamond will refract the light in a way that makes it difficult to read the text beneath. If you can read through the stone clearly, it’s likely a fake.
Additional Methods to Check a Marquise Diamond’s Authenticity
4. Heating the Diamond
Hold the diamond with fireproof gloves or pliers and heat it with a lighter for about 40 seconds. Then drop it into cold water. A real diamond won’t crack, but fake diamonds like glass will shatter.
5. The Sandpaper Test
Rub the diamond against sandpaper. A real diamond will not be scratched by the sandpaper, as it is much harder than the abrasive material. If the stone gets scratched, it’s likely not a diamond.
6. UV Light Test
Place the diamond under UV light. While some real diamonds will glow, not all will, so this test is not always reliable. However, if it does glow, it’s likely a genuine diamond.
7. The Sparkle Test
Observe how the marquise diamond sparkles in natural light. Real diamonds refract light in a way that creates flashes of color (fire) and sparkle (brilliance). If the stone doesn’t sparkle or only reflects white light, it might be a fake.
Final Thoughts
If you’re not confident in your ability to identify a real marquise diamond on your own, it's always a good idea to enlist the help of a professional jeweler. They can perform thorough tests to confirm the authenticity of your stone and give you peace of mind in your purchase. Whether you’re looking for a unique engagement ring or adding a statement piece to your collection, knowing how to identify a genuine marquise diamond is crucial in ensuring you’re getting what you paid for.