A diamond’s value goes beyond its sparkle. Whether inherited, gifted, or self-purchased, knowing if your stone is authentic is about certainty, not spectacle. While a certified jeweller like Ecksand remains the final word, several simple at-home tests can help you determine whether your stone might be the real deal.
Below, we explore how to test a diamond at home using everyday items, from the flashlight test to the classic dot test.
One of the most popular methods is the flashlight test. Real diamonds, whether natural or lab-grown, refract light sharply, creating a brilliant sparkle with a white or grey tint. Fakes like cubic zirconia or moissanite often reflect rainbow hues instead.
Hold the stone under direct light in a dark room. A diamond will cast strong, bright sparkles and distinct flashes. Simulants may appear glassy or give off colored reflections that are too uniform.
Diamonds disperse heat rapidly, it’s one of their signature traits.
Gently breathe on the diamond. If the fog disappears instantly, it’s likely a real diamond. If it lingers for more than two seconds, it could be fake.
This fog test diamond trick is particularly useful for rings and earrings worn daily, where residue can mask a stone’s true brilliance.
Another classic at-home method is the dot test, ideal for loose stones.
Draw a small black dot on white paper. Place the stone flat side down over it. If you can see the dot clearly or its reflection through the top of the stone, it’s likely not a real diamond. A real diamond’s high refractive index will scatter light, preventing a clear view.
This is a quick way to rule out glass or crystal imitations.
Real diamonds are dense and will sink when placed in water.
Fill a clear glass with water, and drop the loose stone in. If it sinks quickly, it’s likely real. If it floats or sinks slowly, it may be a simulant like cubic zirconia or quartz.
While this at-home diamond test isn’t foolproof, it’s a useful step in the process.
Some diamonds glow under ultraviolet (UV) light, most commonly, they emit a blue fluorescence.
In a dark room, place the stone under UV light. A blue glow may suggest the stone is natural, although not all diamonds fluoresce. A green, yellow, or lack of fluorescence doesn’t confirm a fake, but it could warrant further inspection.
Diamonds are formed under immense pressure, making internal inclusions common. Flawless diamonds are rare, and often lab-grown or synthetic.
Use a magnifying glass or jeweler’s loupe to inspect the stone. Natural diamonds often have tiny internal marks, while fakes may look too perfect. You might also see sharp facet lines and a crisp edge where the crown meets the girdle in real diamonds.
A diamond’s setting can speak volumes. Genuine diamonds are typically mounted in durable, high-value metals like platinum or solid gold. If your piece is made of silver or gold-plated material, there's a higher chance the stone is a simulant.
That said, this isn’t a universal rule. Vintage pieces or custom designs may feature real diamonds in less conventional settings. It’s best used as context, not proof.
While these at-home diamond tests can help you rule out obvious fakes, they’re not substitutes for professional evaluation. Jewelers use specialized tools, like thermal conductivity testers and microscopes, to verify a diamond’s authenticity and grade.
At Ecksand, every diamond, whether in a solitaire diamond ring or delicate diamond necklaces, is ethically sourced and verified by our expert gemologists. You’ll find natural and lab-grown options crafted with intention, transparency, and enduring beauty. Explore our collection of fine jewelry, engagement rings, and diamond wedding bands, each one rooted in real Canadian craftsmanship.
Knowing how to tell if a diamond is real isn’t about becoming an expert overnight, it’s about making informed choices. Use these tests as a first step, and when you're ready, work with a trusted jeweler to confirm the details. Real diamonds last forever. So does confidence in what you're wearing.
Basic tests like the fog test, flashlight inspection, and water drop method can offer insight. They don’t require lab tools, just a careful eye and a few minutes of your time.
Not reliably. 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. Some dispersion of color may occur, but it should appear intense, not dull or scattered.
Start by inspecting the metal. Real diamonds are usually paired with solid gold or platinum. Stamps like "14K," "18K," or "PT" can indicate quality. From there, try one of the simple at-home tests. For full certainty, a jeweller can evaluate both the stone and its setting.
Also known as the fog test, it’s a quick way to gauge heat conductivity. Breathe gently onto the stone. If it clears almost immediately, that’s a promising sign. A stone that remains foggy may not be a diamond.
Shine a flashlight on the stone in a dim space. Diamonds refract light with intensity, showing strong white flashes and occasional color dispersion. A flat, muted response could point to an imitation.
Loose stones are easier to test with certain methods, but mounted diamonds can still be evaluated. The fog and flashlight tests work well without removing the stone. If you're uncertain, professional jewellers have tools designed to test diamonds in their settings.
Genuine diamonds are typically set in metals like solid gold or platinum. Less expensive settings, such as gold-plated or unmarked alloys, are often used for simulants. That said, vintage and custom pieces can vary, so use this as one of several clues.
A diamond’s value goes beyond its sparkle. Whether inherited, gifted, or self-purchased, knowing if your stone is authentic is about certainty, not spectacle. While a certified jeweller like Ecksand remains the final word, several simple at-home tests can help you determine whether your stone might be the real deal.
November's birthstones, topaz and citrine, are more than just seasonal gems. They're storied minerals with rich histories, symbolic depth, and enduring appeal. At Ecksand, we craft jewelry that honors these stones' legacies while embracing modern design. Whether you're marking a birthday, anniversary, or personal milestone, these gems offer a meaningful way to celebrate.
When shopping for fine jewelry, it's natural to compare diamonds and their lookalikes, such as moissanites and cubic zirconia (CZ). All of these stones may sparkle, but their origins, structure, and long-term value tell very different stories. Whether you're buying your first diamond ring or researching ethical engagement ring options, understanding the key differences between CZ and diamond is essential.
When shopping for a diamond ring, one of the most common questions people ask is: How big is a 1 carat diamond? While "1 carat" refers to a diamond's weight, not its size, many buyers understandably want to know how that translates visually. Here's what you need to know about 1 carat diamond size, how it looks on a finger, and what affects its appearance.
Everything you need to know to find the perfect engagement ring for your dream proposal.
Our seasoned artisans provide expert guidance on diamonds, gemstones, jewelry, and more.
Learn more about how to style and size your jewelry.
Ecksand's commitment to using sustainable materials without compromising on quality.
