You can get clues if a diamond is real with at-home tests like the fog test (real diamonds don't fog easily), the water test (real ones sink quickly), the dot test (can't see through a real one), and by checking its sparkle for brilliant white light (not just rainbow colors), but these aren't foolproof; the most reliable method is a professional appraisal, though a UV blacklight test can show a blue glow for many real diamonds.
Mobile apps may mimic testing, but they can't match the accuracy of professional instruments. Your phone won't replace a professional appraisal, but it can assist. Use the flashlight to observe how the stone handles light. A real diamond will produce sharp flashes and concentrated brilliance.
View It Through a Loupe
Hold the loupe up to the gemstone, and look for imperfections. Remember, small flaws are natural and often indicate that the stone is real. Look for subtle color gradations, tiny mineral fragments within the stone, and other natural imperfections. If your diamond is flawless, it's probably fake.
To determine a diamond's authenticity using a mirror, observe the mirror reflection test. Genuine diamonds display unique reflective quality, lack surface scratches, show no fogging effect, and their mirror symmetry highlights their real, unmatched brilliance.
Flashlight Test
To tell if a diamond is real with a flashlight, observe how the stone refracts light. Shine a flashlight directly at the diamond. A real diamond will reflect white light brilliantly, while a fake stone may not reflect as intensely or at all.
The Aquamarine name comes from the Latin word for seawater and is said to calm waves and keep sailors safe at sea. It is sometimes referred to as a poor man's diamond because of the pale color.
Real diamonds don't fog up as long. If you take the stone and breathe on it—whether it's real or fake—it will fog up, just like a mirror. The difference, however, is in how long the fog lasts on the stone's surface. With real diamonds, the fog will disappear quickly because diamonds conduct heat.
Whereas diamond will pass a pen test and have rainbow sparkle, white sapphire will not pass and has white and silver sparkle.
Pure diamond is not magnetic.
Place the gemstones in a glass of water and watch. If it floats, then it is probably a fake stone. Real diamonds will sink to the bottom of the glass, while cubic zirconia will float to the surface.
Carat is the unit of measurement for the physical weight of diamonds. One carat equals 0.200 grams or 1/5 gram and is subdivided into 100 points. For comparison, in units more familiar in the United States, one carat equals 0.007 ounce avoirdupois.
Diamond Water Test
This may be the easiest test, but it requires that we have a loose gemstone. Since diamonds have a high density, they will naturally sink when placed into a cup of water. If the stone happens to float, that means it is indeed fake.
The "3-month ring rule" is an outdated marketing guideline suggesting spending the equivalent of three months' salary on an engagement ring, a concept created by De Beers to boost diamond sales, evolving from earlier one and two-month suggestions. Today, it's widely seen as a myth, with most couples prioritizing personal financial comfort, open communication, and meaningful choices over this arbitrary rule.
The Sparkle Test
Synthetic or fake stones, sparkle less than real, or mined diamonds. With light reflection, look for shades of gray. Synthetic stones, such as cubic zirconia, sparkle with more iridescent colors. Natural diamonds reflect light in more grayish hues.
Can you test a diamond with your phone? You can use your phone's flashlight, or any bright light, as a quick way to observe how a diamond interacts with light.
Position the Diamond Under the Flashlight – Hold the stone at different angles while shining a beam through it. Look for Sparkle and Reflection – A genuine one will reflect brilliant white and rainbow colours due to its superior light dispersion.
Buying a diamond starts by understanding the unique characteristics of each stone. After all, no two diamonds are the same. To help you make sense of shopping for these timeless gems, diamonds are graded based off the 4Cs - cut, color, clarity, and carat weight. The 4Cs of diamonds impact a stone's beauty and value.
Simulated diamonds are also known as diamond simulants and include things like cubic zirconia (CZ), moissanite, and YAG. They can also include some natural clear gemstones like white sapphire, white zircon or even clear quartz. Simulated diamonds do not have the physical and chemical properties of real diamonds.
A 20-carat diamond is quite large, weighing 4 grams (0.2 grams per carat) and appearing roughly the size of a U.S. dime to a bit larger, with dimensions around 20-22 mm long for an oval or about 20-21 mm in diameter for a round cut, though size varies significantly with shape and cut quality.
I1 clarity simply means “Included to the 1st degree” and describes the clarity of a diamond with small inclusions visible to the naked eye. For many buyers, I1 clarity diamonds offer an affordable alternative to high-clarity diamonds priced higher than included diamonds.