Last updated on December 25, 2022
Have you ever wondered if the diamond you have received from your ancestors is genuine? Let’s see if it is possible to tell if a diamond is real with at-home tests or if you still need special equipment and the help of experts to get a conclusive answer.
At-Home Tests to Tell If a Diamond Is Real
The water test is one of the simplest ways to spot fake diamonds.
Get a drinking glass and fill it with clean water. Carefully drop the loose gemstone into the glass. If it sinks, it is probably a real diamond. If it floats underneath or at the surface of the water, you deal with a fake diamond.
Although this test might seem quite simple, it is based on the gemstone’s density level. Diamonds are very dense (3.51 g/cm³) and usually outmatch the fakes in the density test. However, keep in mind that good-cut cubic zirconia or glass is actually pretty heavy and could pass the water test as well.
The fog test is another easy method to tell a fake diamond from a real one. Real diamonds are heat resistant, meaning they never fog up the way glass or diamond alternatives do.
For the fog test, hold the stone between two fingers and breath on it. If the fog disappears right away, the diamond is genuine. If it takes a couple of seconds for the fog to dissipate, your stone is likely a fake diamond.
Before continuing with this test, you should be aware that this method would damage a fake stone.
Real diamonds are incredibly strong materials, and extreme temperature changes do not affect their structural integrity.
To test this, take a drinking glass and fill it with cold clean water. Use fireproof gloves to hold the stone and heat it for 30 seconds with a lighter. Carefully drop the stone into the cold water. A genuine diamond would not be affected by the temperature change and sink to the bottom of the glass, while a fake one would shatter.
Extreme heat and a sudden switch to cold water will ruin any stone other than a diamond, so do not do this unless you are ready to damage a fake gem.
Newspaper or Read-Through Test
The newspaper or read-through test is what it sounds like – you need to read a text through the diamond. Be aware that this test suits only loose stones.
Take the stone and place it flat side down onto a newspaper or any other paper with lots of lettering. If you can read the letters, even if the letters are blurry, the diamond is fake.
It is impossible to read through a real diamond because its facets will refract the light in different directions. It is worth mentioning that this test will not be reliable if the stone has an atypical or step cut.
The sparkle test is a visual inspection of your stone in the light.
Take the diamond in question and hold it under a normal lamp and try to analyze what you see. A genuine diamond reflects light very well, providing bright shimmers of white light and colourful light reflections.
A diamond simulant such as cubic zirconia sparkles with more iridescent colours, while an authentic diamond reflects light in a more “elegant” way. So if your stone sparkles in many colours, it is probably fake.
Expert Techniques to Tell If a Diamond Is Real
While at-home tests are fun and cost nothing, none of them is 100% conclusive. That is why it is recommended to send the stone in question to a professional gemologist and get a definitive answer.
Inspecting a Diamond With a Loupe or a Microscope
Diamond professionals use a special 10x magnifying glass or a microscope to inspect diamonds and other gemstones. Under magnification, an expert will look for blemishes and imperfections within the stone.
While a fake diamond can be perfectly flawless, a real gem will have tiny imperfections and structural features which might not be visible to the naked eye. So if the stone is too perfect, most likely, it is not a genuine diamond.
Using a Diamond Tester
A diamond tester is a portable device used to check the authenticity of diamonds and test materials for their thermal and electrical conductivity. It can accurately indicate if the stone is a genuine diamond based on the gem’s physical properties.
The principle of its operation is based on the fact that different gemstones have different chemical structures, and thus they conduct heat and electricity differently. It means that heat or electricity will pass through a diamond in a different way than it would through cubic zirconia, for example.
It is important to mention that the tester that measures only thermal conductivity cannot tell a real diamond from moissanite as these two stones are very similar when it comes to interaction with heat. To get accurate results, you will need a tester that measures the electrical conductivity of a stone or combines both aspects because diamonds and moissanites conduct electricity differently.
Featured image: Andrey Popov / Canva