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A diamond can look convincing under bright jewellery-store lighting. So can quite a few things that are not diamonds.

Cubic zirconia, glass, moissanite and other diamond alternatives can sometimes look remarkably similar at first glance, especially if you do not regularly handle gemstones. That is why one of the most common questions people ask while buying diamond jewellery is:

"How do I know this diamond is actually real?"

There are plenty of internet tricks claiming to give you an instant answer.

Put the diamond in water. Breathe on it. Scratch something with it. Hold it over newspaper.

Some of these tests are loosely based on real properties of diamonds, but none of them should replace proper identification by a qualified jeweler or gemologist.

So instead of relying on one dramatic "diamond hack," here are five sensible ways to understand whether the stone you are looking at is likely to be genuine — and how professionals confirm it properly.

1. Start With the Diamond Certificate

Before examining sparkle, reflections or anything else, ask one simple question:

Does the diamond have a grading report?

For valuable natural diamonds, certification from a recognized independent gemological laboratory is one of the most useful pieces of information you can receive.

A grading report generally records important characteristics such as:

• Carat weight
• Colour grade
• Clarity grade
• Cut information
• Measurements
• Proportions
• Identifying characteristics

Some certified diamonds may also carry a microscopic report number inscribed on their girdle, which can be matched with the certificate. This is much more reliable than trying to determine authenticity purely by looking at the diamond.

It is also important to understand that a jeweler invoice and a diamond grading certificate are not necessarily the same thing. If you are making a significant purchase, ask exactly what documentation accompanies the stone.

A trustworthy jewelery buying experience should make these details easy to understand.

2. Look at the Sparkle Carefully

Diamonds are famous for sparkle, but "more sparkle" does not automatically mean "real diamond."

Different gemstones interact with light differently. A well-cut diamond typically produces a combination of bright white reflections along with flashes of spectral colour.

Some diamond simulants can produce even stronger rainbow-like flashes.

Moissanite, for example, has different optical properties from diamond and may display noticeable colourful fire under certain lighting.

Cubic zirconia can also appear very bright when new, although its optical behaviour differs from that of a diamond.

The challenge?

Most people cannot reliably identify these differences without experience. Lighting also makes a huge difference. Jewelery stores often use carefully positioned lights specifically to make stones look their best.

So sparkle can provide clues, but it should never be your only authenticity test.

If you are comparing stones, try looking at them under more than one kind of lighting rather than judging them exclusively under intense spotlights.

3. The Fog Test Can Give a Clue — But Not a Verdict

One of the most famous home tests involves gently breathing onto the diamond as you would fog a mirror. Diamonds conduct heat efficiently, so the condensation caused by your breath may disappear relatively quickly compared with certain materials.

That is where the popular "fog test" comes from.

However, there is a problem.

Real jewelery is usually mounted in metal.

The stone may be dirty.

Room temperature can vary.

Other gemstones and synthetic materials can behave differently depending on their thermal properties.

All of these things can affect what you see. So if the fog disappears quickly, that does not automatically prove you have a natural diamond. And if it stays slightly longer, that does not automatically mean the stone is fake. Use this kind of test only as an interesting observation, not as the basis for a jewelry purchase.

4. Do Not Rely on the Scratch Test

You may have heard people say:

"Diamonds are the hardest material, so just see if it scratches glass."

Please do not do this with jewelry you care about.

Yes, diamond ranks 10 on the Mohs scale of mineral hardness. But hardness refers to resistance to scratching — not resistance to breaking. Diamonds can still chip or fracture, particularly along certain directions.

The setting around the stone can also be damaged during an improvised scratch test. And several other materials are hard enough to scratch glass anyway.

So scratching glass does not conclusively prove that a gemstone is a diamond. Professional diamond identification does not require you to risk damaging the jewelry.

This is a good example of why internet tests should be treated cautiously.

5. Let a Professional Diamond Tester Confirm It

If you genuinely need to know whether a stone is a diamond, professional testing is the sensible route. Jewelers and gemologists use instruments designed to analyze properties such as thermal conductivity and, in some cases, electrical conductivity.

Traditional thermal diamond testers can help separate diamond from many common simulants.However, distinguishing diamonds from materials such as moissanite can require more advanced testing.

There is another layer too.

Today, there are natural diamonds, laboratory-grown diamonds and diamond simulants.

These are not all the same thing.

A lab-grown diamond is still a real diamond in terms of its fundamental material and crystal structure. It is simply created in a laboratory rather than formed naturally beneath the Earth.

A simulant such as cubic zirconia, however, is a completely different material designed to resemble a diamond.

So asking whether something is "real or fake" can sometimes oversimplify the question.

A better question might be:

Is this a natural diamond, a laboratory-grown diamond or a diamond simulant?

Specialised gemological equipment may be required to make that distinction accurately.

What About the Newspaper Test?

Another popular trick suggests placing a loose diamond over printed text.

The theory is that because of the way a properly cut diamond refracts light, you should not be able to clearly read the letters through it. There is some optical reasoning behind this idea.

But again, it is not reliable enough for identification.

The result depends on factors such as:

• Diamond shape
• Cut
• Proportions
• Whether the stone is loose or mounted
• The viewing angle

A poorly cut diamond may behave differently from what the test expects.

And some non-diamond stones may still "pass."

Consider it a curiosity, not proof.

The Bigger Question: Do You Know What You Are Buying?

This is where diamond shopping becomes much simpler.

Instead of trying to become a gemologist before buying a ring, focus on purchasing from a jeweller who clearly explains what is being sold.

Ask:

• Is the diamond natural or laboratory-grown?
• Does it come with certification?
• What laboratory graded it?
• What is the carat, colour and clarity?
• Can I see the grading report?
• What metal purity is the jewellery made in?
• A confident jeweller should be comfortable answering these questions.

You should never feel awkward for asking them.

Buying jewelery often carries emotion, engagements, anniversaries, birthdays, weddings, milestones or simply something you have wanted for yourself for years.

That emotion should not replace information.

The two should go together.

Trust Documentation Over Tricks

Spotting a "fake diamond" is not as easy as watching one TikTok test and becoming an expert. Some imitations are easy to identify.

Others can fool an untrained eye.

And distinguishing a natural diamond from a laboratory-grown diamond generally requires specialist testing rather than home experiments. So while observing sparkle, reflections and other characteristics can be interesting, the strongest approach is still remarkably simple:

Check the documentation, understand what is being sold and have the stone professionally verified when necessary.

At Pravi Jewels, choosing diamond jewellery should feel exciting, not confusing.

Because the best part of buying a diamond should be deciding which piece you love not wondering whether the stone in front of you is what someone says it is.