How To Identify Real Diamonds?

So you’ve come across a stunning diamond and you want to make sure it’s the real deal. Well, fret not! In this article, I’ll share some valuable tips on how to identify real diamonds. From examining the sparkle to conducting a simple at-home test, you’ll be equipped with the knowledge to distinguish between genuine diamonds and imitations. Get ready to dazzle your friends with your newfound expertise in spotting the real diamonds from the fakes!

Physical Properties


One of the key physical properties of a real diamond is its exceptional hardness. Diamonds are the hardest naturally-occurring substance on Earth, scoring a perfect 10 on the Mohs scale of mineral hardness. This means that diamonds can only be scratched or damaged by other diamonds. So, if you’re wondering if that sparkling gemstone in front of you is a real diamond, try scratching it with another diamond. If there are no scratches, chances are it’s the real deal!


Diamonds also have a unique density that sets them apart from other gemstones. Their density is determined by their carbon composition and crystal structure. Real diamonds have a high density, typically around 3.52 grams per cubic centimeter, which means they will feel heavier than most imitations or simulant alternatives when you hold them in your hand. So, if you’re unsure about the authenticity of a diamond, compare its weight to that of a known real diamond and see if there’s a noticeable difference.

Refractive Index

The refractive index of a diamond is another handy tool for identifying its authenticity. Refractive index refers to how light is bent or refracted as it enters and exits a gemstone. Real diamonds have a high refractive index of around 2.42, which means they have excellent light reflection capabilities. To test this, place the diamond under bright light and observe how the light glimmers and sparkles within the stone. If the gemstone exhibits dazzling light reflections, it’s likely to be a genuine diamond.

Visual Assessment


Brilliance refers to the amount of light that enters a diamond and is reflected back to the observer’s eye. Real diamonds possess superior brilliance due to their exceptional light-refracting properties. When light enters a diamond, it bounces off its facets and creates a captivating display of sparkle. Genuine diamonds will exhibit a high level of brilliance, with bright flashes of light bouncing around the stone. So, if you’re assessing a gemstone’s authenticity, look for that mesmerizing brilliance that only a real diamond can deliver.


Fire is another visual characteristic unique to real diamonds. It refers to the dispersion of light into its spectral colors as it passes through the diamond. Genuine diamonds scatter light in a way that creates vibrant flashes of rainbow-like colors, known as fire. The play of colors within a diamond is a result of its ability to bend different wavelengths of light. So, when examining a potential diamond, look for those enchanting bursts of color that dance within the stone.


Scintillation is the term used to describe the sparkling effect created when a diamond is moved or observed in different lighting conditions. Real diamonds produce captivating scintillation because of their precise cut and the way light interacts with their facets. As light hits a diamond’s facets, it is reflected back, creating a radiant and dynamic display. Authentic diamonds will exhibit scintillation in various lighting environments, showcasing their brilliance and captivating nature.


Color is an essential factor to consider when identifying real diamonds. While colorless diamonds are highly prized, diamonds can come in a range of colors. However, genuine diamonds tend to have a consistent and uniform color throughout the stone. This color is a result of the presence of impurities or chemical defects within the diamond’s structure. It is important to note that some diamonds, known as fancy colored diamonds, are intentionally treated to enhance their color. So, when assessing a diamond’s authenticity based on its color, consider factors such as consistency, uniformity, and the presence of any artificial enhancements.

Inspection Tools


Loupes are small magnifying tools that are frequently used by jewelers and gemologists to closely examine gemstones and diamonds. These handheld devices typically have a circular frame with a lens that can magnify the object being viewed. By using a loupe, you can spot key characteristics of real diamonds, such as their inclusions, cut quality, and overall clarity. Look for loupes with high magnification power, typically 10x or higher, to help you distinguish the fine details that may indicate a real diamond.

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For a more detailed and comprehensive examination, jewelers and gemologists use microscopes equipped with high-powered lenses. Microscopes offer a greater level of magnification and clarity compared to loupes, allowing for a closer inspection of a diamond’s internal and external features. By analyzing a diamond under a microscope, you can assess its clarity, cut precision, and even detect any treatments or enhancements that may have been applied. Microscopes with adjustable lighting and polarizing filters are particularly useful in diamond identification.

Diamond Tester

A diamond tester is a handheld electronic device that can quickly and easily determine whether a stone is a real diamond or a simulant. These testers work by detecting the thermal conductivity properties of diamonds, which differ from those of most simulants. By touching the diamond with a heated probe, the tester can assess how quickly the stone conducts heat and provide a reading indicating its authenticity. Diamond testers can be a useful tool for initial assessments, but they are not foolproof and should be used in conjunction with other identification methods.

Fog Test

The fog test is a simple and quick test to determine if a diamond is real or fake. To perform this test, breathe hot air onto the stone, creating condensation. If the condensation immediately dissipates or evaporates, leaving no trace, it suggests that the stone is likely a real diamond. Real diamonds disperse heat rapidly, causing the fog to disappear almost immediately. On the other hand, if the fog remains on the stone for an extended period, it may indicate that the gemstone is not a genuine diamond. However, it is important to note that this test is not highly reliable and should be used in conjunction with other methods of identification.

Scratch Test

The scratch test is a classic method used to identify real diamonds, as diamonds are the hardest mineral known to man. To perform this test, take a known real diamond and try scratching the surface of the stone in question. If the stone being tested remains unscathed, it is likely a genuine diamond. However, be cautious when conducting this test, as scratching can damage or devalue the stone if it turns out to be a simulant or a softer gemstone. It is always advisable to seek professional help or use alternative identification methods to avoid potential harm to the gemstone.

Heat Test

The heat test is another method that can help determine if a diamond is real or fake. Real diamonds are excellent conductors of heat, so they disperse heat rapidly. To perform this test, heat the stone with a lighter or a torch for approximately 30 seconds. Immediately after heating, drop the stone into a glass of cold water. A real diamond will quickly dissipate the heat and remain cool to the touch, while other gemstones or simulants may retain heat or even crack due to thermal expansion. However, it is crucial to exercise caution when using heat and always seek professional advice if you are unsure.

Water Test

The water test is a simple, non-destructive test that can provide some insight into a diamond’s authenticity. Fill a clear glass with water and carefully drop the stone into it. Genuine diamonds should sink to the bottom due to their high density, while most simulants or fake diamonds will float or remain suspended within the water. Be cautious when performing this test and ensure that the stone is secure within a setting or held with tweezers to prevent any accidental submergence into the water and potential damage.

Reflection Test

The reflection test is a useful method to identify the light reflection and refractive properties of a diamond. Place the diamond on a white piece of paper with light shining directly onto it. Observe the diamond from various angles and orientations, paying close attention to the reflections bouncing off the stone’s facets. Authentic diamonds will reflect both white light and colorful spectral flashes due to their superior refractive index. If the gemstone shows a beautiful display of light, it is likely to be a genuine diamond. However, this test should be used in conjunction with other methods for a more reliable determination.

Professional Evaluation

Certification and Grading Labs

When it comes to truly assessing a diamond’s authenticity and quality, seeking a professional evaluation from a reputable certification and grading lab is highly recommended. These labs employ expert gemologists who utilize state-of-the-art equipment and rigorous evaluation processes to determine the authenticity and characteristics of a diamond. They provide detailed reports that include important information such as the diamond’s carat weight, color grade, clarity grade, cut grade, and more. Reputable certification and grading labs include the Gemological Institute of America (GIA), the American Gem Society (AGS), and the International Gemological Institute (IGI), among others.

Diamond Simulants

Cubic Zirconia

Cubic zirconia (CZ) is one of the most popular and widely used diamond simulants. It is a lab-created gemstone that closely resembles the appearance of a real diamond. While CZ may exhibit similar brilliance, fire, and scintillation to a diamond, it can usually be distinguished by its lower refractive index, softer composition, and lack of natural inclusions. CZ is also more affordable than real diamonds, making it a popular alternative for those seeking a diamond-like appearance at a fraction of the cost.

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Moissanite is a lab-created gemstone that is gaining popularity as a diamond simulant. It is composed of silicon carbide and possesses exceptional brilliance and fire, closely resembling real diamonds. Moissanite has a higher refractive index than diamonds, resulting in increased light dispersion and a unique sparkle. While moissanite is a beautiful alternative to diamonds, it can usually be detected by its higher double refraction and slightly different optical properties when compared to real diamonds.

White Topaz

White topaz is a natural gemstone that is sometimes used as a diamond simulant due to its transparency and affordability. While white topaz can resemble a diamond in appearance, it lacks the exceptional hardness, brilliance, and fire that characterize real diamonds. White topaz has a lower refractive index and may exhibit more visible inclusions compared to diamonds. It is important to note that using white topaz as a diamond simulant is not as common as cubic zirconia or moissanite.

In conclusion, identifying real diamonds requires a careful examination of their physical properties, visual characteristics, and the use of appropriate inspection tools. Factors such as hardness, density, refractive index, brilliance, fire, scintillation, color, and certification play a crucial role in determining a diamond’s authenticity. While tests such as the fog test, scratch test, heat test, water test, and reflection test can provide some insights, it is always recommended to seek professional evaluation from reputable certification and grading labs for a definitive determination. Additionally, being aware of diamond simulants like cubic zirconia, moissanite, and white topaz will help you distinguish between real diamonds and alternative gemstones.