How To Spot A Fake Rolex: 10 Ways
Real diamond jewelry is a meaningful investment for many people. Whether it’s a diamond engagement ring, diamond wedding band, diamond necklace, or diamond watch - diamonds play a key role in the appearance of the jewelry.
Diamonds produce a dazzling optical dispersion effect known as “fire.” They’re a stunning testament to the beauty of nature—natural diamonds take 1 billion to 3.3 billion years to form (25% to 75% of the age of the Earth), meaning they’ve existed since dinosaurs walked the Earth.
Some people don’t mind fake diamonds, synthetic diamonds, or lab-grown diamonds—but many people prefer natural diamonds due to their impressive geological history and appearance. Fake diamonds simply don’t have such an impressive past, so accidentally buying a fake diamond can be a huge disappointment—and it might mean you have grounds for a lawsuit.
So, how do you know if your diamond ring is real or fake? How can you tell if a diamond earring is real? How can you test diamonds to see if they’re real or fake at home? We’ve put together a guide to help you test diamond jewelry at home.
Real vs. Fake Diamonds Differences
How to tell if a diamond earring is real at home? What are the differences between real diamonds vs. fake? The difference between a real diamond and a fake diamond depends on the type of diamond replica or alternative.
Real Diamonds vs. Diamond Simulants and Synthetic
Simulated diamonds are gems that are meant to look like diamonds but aren’t real diamonds. Synthetic diamonds are created in a lab crucible using high temperatures, pressure, powdered elements, and metallic chips. Synthetic diamond simulants are gemstones that aren’t diamonds (but resemble them) and were made in a lab.
Examples of synthetic diamond simulants are:
- Cubic zirconia
- Colorless/white garnet
- Cut and polished glass
Some diamond simulants are not synthetic—they’re not real diamonds, but other natural gemstones that are white/clear and used as a cheaper alternative to diamonds.
Some natural gemstone diamond simulants are:
- White sapphire
- Colorless/white spinel
- White topaz
- White quartz
- Goshenite (colorless beryl)
Sometimes, natural diamond simulants can be synthetic. Most often, white topaz and white sapphire are natural—but some companies create them in a lab, and they’re not much cheaper, despite being synthetic. Furthermore, some popular synthetic diamonds, like rutile, are also found in nature, so they’re not always synthetic. Real diamonds are always going to be harder on the Mohs scale than any diamond simulants.
Real Diamonds vs. Hybrid Diamonds
It can be confusing to understand the differences between all of the diamond alternatives. Hybrid diamonds are created in a lab by growing real diamond crystals over a different kind of gemstone, such as cubic zirconia.
Hybrid diamonds vs. lab-grown diamonds: A lab-grown diamond is a real diamond created in a lab using technology to replicate diamond formation. A hybrid diamond is not 100% real diamond - its surface is made of diamond crystals but its core is another gemstone.
It might seem kind of silly to buy hybrid diamond earrings, and it’s not clear what the benefits are. Hybrid diamonds are sometimes cheaper than lab-grown diamonds, and they appear more like real diamonds than other diamond simulants.
Real Diamonds vs. Lab-Grown Diamonds
What’s the difference between a natural diamond and a lab-grown diamond? The answer is that while both diamonds are real (same structure, same elemental composition), natural diamonds are mined from nature and take billions of years to form, while lab-created diamonds are produced in 6-10 weeks in a lab.
Lab-grown diamonds are synthetic, meaning that they were made by man, but they’re still real diamonds. Lab-grown diamonds are not artificial, although some websites still use this term to refer to them, the Federal Trade Commission has made it illegal to call lab-grown diamonds “fake” or “artificial.” The FTC has also made it illegal to sell earrings with diamond simulants as “real diamonds.”
How to Test a Diamond at Home
If you want to conduct home-testing to determine if your diamond is real or fake, there are several tests you can do no matter what type of diamond earrings you have.
Diamond earring styles:
- princess cut
- colored diamond
- blue diamond
- pink diamond
- yellow diamond
- multi-color diamond
- black diamond earrings
Here are the different ways to tell a real diamond earring vs fake, a real diamond ring vs fake, and any other diamond jewelry you have questions regarding authenticity.
Test #1: Scratch Test
Diamonds are the strongest naturally occurring substance on Earth (fun fact, black diamonds are the hardest variety of diamonds, making them very popular for industrial cutting). Because of this, a hardness test is one way to tell a real diamond earring from fake at home.
The Sandpaper Method
One way to do a diamond scratch test at home is the sandpaper method. Sandpaper has a hardness between 7 and 9 on the Mohs scale, so it may be harder than many fake diamonds and diamond simulants.
- Rub the gritty side of sandpaper against the gemstone.
- Look closely at the diamond for scratches.
- If the sandpaper left scratches on the stone, it’s not a real diamond.
Sandpaper is harder than many simulant diamonds, but it’s not harder than some varieties like white sapphire, moissanite, lab-grown diamonds, or diamond hybrids, so further tests may be needed.
The Glass Method
Maybe you don’t have sandpaper sitting around, so a convenient way to test a diamond earring at home is by scratching its gemstone on glass. The sandpaper method is slightly preferable to the glass method, but it’s more likely to damage your gemstone if it’s not a real diamond, so the glass scratch test may be safer if you’d like to preserve the gem.
- Scrape the diamond against a mirror or panel of glass.
- If it scratches it, it could be a diamond, since diamonds are the hardest material and they should scratch glass panels or glass mirrors.
Many diamond simulants, however, are also harder than glass, so you should look at other tests to identify a real diamond vs. fake as well.
Test #2: Sparkle Test
Diamonds’ brilliance comes from their internal dispersion - the way they reflect and refract light. The sparkle test is a diamond test you can do at home to help determine if your diamond is real or fake. It’s a visual inspection of how the stone appears in the light.
- Hold the stone to a beam of light.
- Twist it around in the light to observe different angles.
- Examine the colors of light in the gem’s reflection.
- Look for shades of grey and rainbow colors.
- Diamonds reflect light very well. You should see both shimmers of white or greyish light, as well as colors inside the diamond. You should not be overwhelmed with colors. If the gem only reflects colored light or produces weak light reflections and weak colors, it might not be a diamond.
Diamonds appearance vs. cubic zirconia: If it reflects more orange colors than white reflections, it’s probably cubic zirconia.
Diamonds appearance vs. moissanite: Moissanite is also highly reflective, but typically shows a wider range of bright colors than a diamond. In a visual inspection of diamonds, look for a balance of white light reflections and colors. The diamond should still appear white overall, with hints of color.
Test #3: Fog Test
Diamonds tend to disperse heat quickly, which makes fog disappear. Cubic zirconia has different properties, so it will retain condensation longer.
- Make sure your diamond earrings and hands are clean first, as oils can tamper with the results.
- Put the stone in front of your mouth and breathe on it until it fogs up.
- Time how long it takes to clear up.
- If it clears up after a few seconds, it’s real. If it stays fogged up for over three seconds, it’s fake.
If you have diamond earrings you know are real, it can help to breathe on both the real diamond and the diamond in question to compare the results.
Test #4: Check the Metal
It’s unlikely that you’ll find a real diamond in a cheap ring setting or earring setting (or any other jewelry). Diamonds typically are set in precious metals such as real gold, real platinum, sterling silver, and for watches - surgical stainless steel.
- Look for hallmarks.
- For real gold, the hallmark will be something like 10K, 14K, etc. European gold hallmarks show a decimal (1.00 for 24K gold, .916 for 22K, .75 for 18K, .417 is 10K, etc).
- For real platinum, PT or Plat, 950 or 999.
- For sterling silver, look for 925 or .925.
- For diamond watches, look for gold, platinum, or steel (904L, stainless).
- If there’s a CZ stamp, it’s cubic zirconia.
- If it’s stamped GP, GF, EP, EPNS, SP, or SF, it’s plated or filled gold or silver—your diamond may not be real, since they’re usually mounted in real gold or silver.
- If there’s no hallmark, you likely have a fake diamond (unless it’s antique jewelry or handmade by a non-professional).
The best metals for diamond earrings are precious metals because they keep the diamond secure and make the jewelry last longer. It’s unlikely that any jewelry maker who knows what they’re doing would mount a diamond in a silver-plated earring or ring band, or other metals.
There are some alternative metals, like tungsten and titanium, that are popular with people whose jobs include manual labor. Usually, these don’t contain diamonds, but some companies do make them with diamonds. They should still have some kind of markings that can help you figure it out.
Test #5: Water test
Diamonds have a high density, so they should sink in water. Not all fake diamonds will float, but it can weed out plastic diamonds and some other varieties quickly.
- Fill a glass with water and drop the diamond into it.
- If real, it will sink to the bottom. Fake stones may float, but not all fake diamonds float, so you’ll want to do more tests.
Test # 6: Heat Test
Real diamonds form under intense heat and pressure underground, so they can withstand flames. This test is a little dangerous, but it can be helpful in determining if a diamond is real.
- Heat the stone with a lighter for about 30-40 seconds.
- Drop it in cold water (not ice cold).
- Examine it. If it shatters, it’s fake. If it’s fine, it could be a real diamond.
This method isn’t super accurate, because many diamond simulants also form from heat, whether naturally or synthetically. This will weed out some fake diamonds that are glass, quartz, and several others.
Other Tips for Testing Diamonds at Home
The tests listed above aren’t all of the at-home diamond tests, but they’re some of the quickest and easiest tests to help determine a diamond’s authenticity.
If you have other equipment, you may be able to test the diamond earrings in these ways:
- Examining it under a loupe - mined diamonds most often have inclusions. If it lacks inclusions, it may be a lab-grown diamond, or it could be another lab-created gem.
- Use a diamond scale. You’ll need to compare the weight of the diamond in question to a real diamond on hand. If it’s cubic zirconia, it will be much heavier for its size and carat. If you don’t have a scale, you can take it to a jeweler to conduct this test.
- Use a blacklight. Many real diamonds emit a blueish glow under UV light. Not every diamond does, but you can tell it’s not a real diamond if it glows orange, green, gray, or yellow.
- Check a diamond’s transparency. Try to read a newspaper or printed words through the diamond. If you can’t read it, it could be real, since diamonds refract light in ways that break up the text and prevent a straight line from showing through them.
Before doing any of the at-home tests, determine if you’re willing to damage the stone if it turns out to be fake. A real diamond (natural or lab-created) can withstand these tests, but many gems can’t. So if you want to keep your jewelry even if it’s fake, only conduct the tests that won’t scratch or shatter it.
Professional Diamond Testing
The best way to test if a diamond is fake or real involves professional diamond testing that’s proven to work. The best way to do this is to take your men’s or women’s diamond earrings in question to a professional jeweler to have them perform the tests.
Many jewelers will test your diamond stud earrings for free. If you have a certificate of authenticity for your diamond jewelry, jewelers will also be able to tell you if it comes from a reliable source or not. Some diamond certificates are fake. Here are some of the tests that work to prove if a diamond is fake or real; these methods are used by professional jewelers.
Test #1: Loupe Inspection
One of the first things a jeweler may use to test if your men’s diamond earrings are fake or real is to examine it under a jeweler’s loupe, a device that magnifies to reveal details in gemstones and jewelry. If you have a loupe at home, you can also look at your diamond under it to search for inclusions. A jeweler, however, has professional experience looking at diamonds, and they do it all the time. They’ll know exactly what to look for, and they may pick up on things that you might overlook.
- The jeweler will look for blemishes, imperfections, and inclusions using the loupe.
- They can tell you if it seems to be lab-grown or a synthetic gem vs a natural diamond.
After conducting this test, they may do further tests to tell for certain if your diamond is real or not.
Test #2: Thermal Conductivity Probe
Gemologists usually have a “diamond tester,” or thermal conductivity probe or meter. You may also find these online, but the reputability varies from seller to seller. To save money, you’re better off taking it to a professional so they can use their own diamond tester and provide an expert assessment.
This method tests the heat dispersion of gemstones.
- If the gemstone disperses heat at a slower rate, it’s not real.
- Moissanite has similar or equal heat dispersion to real diamonds, so moissanite will pass this test despite not being a real diamond.
Some jewelers have testers that can distinguish moissanite better than other commercially available diamond testers. Why spend money on a “diamond tester” if you’ll still end up uncertain if it’s moissanite or a real diamond?
Test #3: Professional Scale
Jewelers and diamond experts usually have an excellent scale that’s finely-tuned to detect weight differences between diamonds and other gems. They’ll also have real diamonds on-hand to compare to the diamond in question.
Diamonds will weigh less than some diamond simulants, like cubic zirconia, but you can only tell using a finely-tuned scale to detect carat weight. If doing this test at home, you might not have a loose real diamond to compare with yours.
Test #4: Electric Conductivity
Another way professionals can tell a real diamond from fake diamonds is to use an electric conductivity test. This test is difficult to do at home and is not recommended.
- The jeweler will test the diamond with electric conductivity equipment.
- A diamond will show conductivity, whereas moissanite, cubic zirconia, and other diamond simulants won’t.
The electric conductivity test is the best way to tell a synthetic gemstone from a diamond. This is one of the few ways to tell a real diamond from moissanite, so if you want to be certain that your diamond is real, it’s important to take it to a jeweler who can affirm that it’s not moissanite using their specialized equipment.
If you really want to tell if your diamond earring is real, the best way is to take it into a professional. This is typically free, and a guaranteed method. However, if you want to do some at-home tests to help you figure out if your diamond is fake, choose your tests carefully—some may damage fake diamond jewelry. To avoid getting ripped off, and to know how to tell if you’re buying real diamond jewelry, we recommend checking out our diamond buying guide to look at the questions to ask a seller before purchasing a diamond.