Validate the original diamond quality – Beyond the certification

Posted by Hari Krishna

July 21, 2020

Often referred to as the 5th C of diamond grading; the diamond certificate is essential when you buy a diamond as the best proof of the diamond’s authenticity is to see its certificate. 

Also, as a buyer, you always tend to make sure that whether the stone is certified by the globally recognized gemological laboratory or not. For example, the most trusted diamond certification authority in the world is the Gemological Institute of America (GIA). 

But what if you are not convinced about the authenticity of the stone you are buying or having any doubts about the diamond certificate or you are planning to purchase the non-certified or self-certified diamonds. Then is there any method you can assure the quality of the diamond? 

Yes of course there are many ways you can assure the quality of the stone you are buying. In such cases, you still can instantaneously grade the stone by yourself. Certainly, the result you will come up with will be in terms of the grading range instead of the exact grading values, and also they will be approximate. 

Let’s explore some of the new ways with the experts at HK to grade the diamonds instantaneously: 

[**Important Note: Before going further, please keep in mind that all the information we are going to share about manual grading of the diamonds is based on years of experiences and none of the following methods necessarily be foolproof of the natural humane errors. So, HK recommends you use them at your own risks and is not taking responsibility for any loss or damages that occurred.]

Instantaneous grading: 

Instantaneous grading on your own is a great systematic approach to understand the diamond quality better. After spending some time getting to grip on what key variables among 4Cs drive the quality, appearance, and the price of a diamond, you will be well on your way to making a more responsible diamond purchase.

Carat weight: 

The Carat weight of the diamond is very easy to rate for any individual compared to rest 3Cs. There is a standard conversion of carat into normal gram weight; and it is – 1 carat is equal to 0.2 grams.  

So, all you have to do while purchasing a stone is weigh the stone you are buying on a normal weighing machine at the shop and divide its weight (in grams) by 0.2 and you will know the carat weight of the stone. 

For example, if your diamond weighs 0.40 grams on a normal weighing machine then it is of a 2 (0.40/0.2) carat weight diamond.


Generally, the color of a diamond is graded by comparing the stone with a set of graded master stones at the shop and determining which one of them is closest in color to that stone. 

But if you don’t have access to the graded master diamonds at the store then you can try to determine its approximate range of colors by just looking at the stone and figure out how colorless it looks. As it is hard to pinpoint the exact color grade without comparing it with graded master stones. 

If your diamond doesn’t appear to have a visible yellow tint, then the stone color grade will most likely fall in the D to H range. 

If your diamond has a barely visible yellowish hue then it is most likely to fall under the I to  M grading range.

If your diamond has some very light yellow color nonetheless visible then it would likely be graded in the range of N to R.

But if your diamond has a clearly visible yellow tint then it most likely to be graded under the S to Z color range.


The grading of the cut of the diamond is a very detailed and precise process that needs some expertise of the field so it is very tough to rate the cut of the diamond instantaneously in the store unless you are an expert in the field. So, in the cut-grading of the diamond, you have to believe what the retailer is claiming. 


The clarity of a diamond is graded on how many natural flaws can be seen within a diamond just by looking at the stone in both ways; under magnification and with the naked eye.

But if you want to measure the diamond clarity instantaneously on the store then you should compulsorily have the access to the 10 magnificent lenses. 

Again, if you don’t have access to the lens then you have to rely on the retailer’s claim. But If you have access then, 

If you look at a diamond under the 10 magnification, and cannot readily see any visible flaws inside, then the stone’s clarity would most likely be graded in the range of FL/IF/VVS1/VVS2.

If the diamond you are looking under the 10 magnification has some visible inclusions under the magnification but not to the naked eye, then the stone’s clarity is most likely in the rage of VS1/VS2/SI1.

Flaws in SI2 clarity diamonds may generally not be visible to the unaided eye, but if they are visible then they will usually be located towards the sides of the stone.

If the diamond has inclusions that are easily noticeable with the naked eye, then the stone is most likely to be graded in the range of I1/I2/I3. These stones are more likely to have visible inclusions located towards the center of the table when you look at the stone from the top.


Fluorescence doesn’t have any visual effect on the diamond appearance in normal light, but if you consider the statistics, then about 30% of diamonds emit some degree of fluorescence when they are exposed to concentrated UV light. 

That is the reason why most of the gemological laboratories in the world don’t even mention the fluorescence color and intensity on their certificates. Even GIA and HRD include a single line on their certificates that just indicates the color and intensity of the diamond’s fluorescence. 

So now the important question comes; what will be influenced by the color and intensity of fluorescence? And the answer is Lustre. Luster refers to the level of milkiness and cloudiness in a diamond that occur due to the negative visual impact of fluorescence. 

The luster in the diamond grades as follows:

L1: Perfectly crisp and clear with no milkiness. 

L2: The cloudiness is there but can be very hard to spot for inexperienced eyes.  

M1: Milkiness can be easily spotted. 

M2: Moderately milky.

M3: Very cloudy and milky. 

Since a luster grade is never issued as a grading certificate, it’s rarely discussed and often overlooked.

Beyond instantaneous grading:

There are many ways to ensure that whether your diamond is real or not; apart from the instantaneous grading. So, let’s have a look. But again, remember that none of the presented methods is 100% accurate.

Light distortion:

We all know the fact that the real diamonds distort the light, so in that case, you should not be able to see the stone’s bottom through its top. You can also place it over a printed text, and you should not be able to see the printed symbols clearly through the diamond if it’s real. 

However, if the diamond has an atypical cut, then this test is not reliable.

Heat dissipation:

If your diamond is real, it should not be easily heated up. So, you can hold the diamond in front of your mouth and breathe on it in order to fog it, and if the fog doesn’t disappear right away, then your diamond is probably fake.


No natural diamond ever be perfect, it always has some internal flaws. On the other hand, fake diamonds usually don’t have any flaws. So, if your stone is perfect and clear, then it’s probably not a real diamond.

Diamond Testers:

Diamond Testers are portable devices that test the thermal or electrical conductivity of the stone and indicate whether the stone is a real diamond based on these physical properties.

But the testers that only measure thermal conductivity are not efficient; as a real diamond and moissanite both stones are very similar when it comes to interaction with heat. However, the devices that test for both electrical and heat conductivity are more accurate.

Nowadays, almost every diamond retailer has a diamond tester, so you can test your diamond on the premises itself.

At HK, we strongly believe in hard work and persistence. Our unique designs crafted with the highest quality have fetched us unanimous praise in the global market. 

Our commitment towards offering innovation with quality and consistency recognized us as one of the leading Jewellery Exporters from India to the USA, Hong Kong, UK, Israel, UAE, and Belgium.

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