Diamond has 4 basic grades, weight, colour, purity and cut

Before finding out how to identify a real diamond, let’s learn more about this special stone. Originating from Greek, the word diamond means “adamas”, which means “indestructible” and its earliest versions formed more than 2.5 billion years ago.

Desired by many, this is one of the best known noble stones in the world. Generally speaking, we are talking about a kind of crystal, belonging to the category of native minerals. 

Cut Diamond Stones
Cut Diamond Stones

Such matter is composed of pure carbon, but in crystallised form. Incidentally, this is the most solid material on the entire planet, and it is also one of the most expensive stones in existence;

Rough diamonds can be found in mines. However, when they are extracted, they tend to have a different shape from the one we find in jewellery stores – that is, opaque. The brilliance, however, comes after cutting;

Nowadays, there are diamonds produced in laboratories. Contrary to popular belief, they do not consist of modified pieces, but rather have the same chemical compound as those found in nature.

Characteristics of the real diamond

  • In nature, diamond can form in different ways. Still, for this to happen, it is necessary that the environment presents very high pressures and temperatures. The most frequent way occurs in terrestrial mantles, which are located at a depth of 150 kilometres.
  • Their structure is formed by pure carbon atoms, distributed in their vertices and, only one, in their central area. This makes the stone compact and with a high density (3.5g / cm3).
  • Diamond has high hardness. According to the Mohs Scale, the stone has a hardness of 10 – the maximum value that the measure can reach:
Mohs hardness table
Mohs hardness table
  • It is a stone that cannot be scratched by any other, let alone by different materials. Only a true diamond can cause scratches on another; 
  • .Diamond has a high refractive index. Thus, after its cutting, it is possible to obtain an extremely brilliant piece.

Como identificar um diamante

How to identify a real diamond

But, after all, how to identify a real diamond? Taking this care is essential, even more so because the number of gemstone fakes is increasing;

And, given this, of course, you do not want to run the risk of being mistaken during a purchase, do you? 

By having the guarantee of acquiring a real diamond, you will be able to have in your hands a valuable jewel, made from the best materials on the market and that, as a result, can last for many, many years, and can even be part of your family history.

The good thing is that there are different methods that can be practised by those who want to learn how to identify a real diamond. We have listed this step by step to help you in this task:

1. Use the puffing technique

A very simple trick to understand how to identify a real diamond is the whiffing technique. It works like this: you will have to place the diamond in front of your mouth and let out the air. The process is the same as we perform on a mirror or glass, when we want to write something on its surface.

If the stone remains blurred for more than two seconds, the chances of it being a fake are high. A real diamond is known for its power to disperse heat quickly, preventing the blurred effect for a long time.

2. Consider the metal that accompanies the jewel 

You will hardly find a diamond jewel accompanied by a low-value metal, such as stainless steel. For this reason,you must always consider the material where the gemstone is set;

The tip is to look inside the jewellery and identify the carat of the metal. The noble options usually have the following initials: <nbsp;

  • 10K; 
  • 14K; 
  • 18K; 
  • 585; 
  • 750; 
  • 900; 
  • 950; 
  • EN; 
  • Plat

On the other hand, if you find the initial C.Z, for cubic zirconia, it is very likely that the diamond is not real.

3. Keep an eye on the brilliance

A true diamond has reflections in greyish hues – and never coloured ones (even the coloured diamonds). With this in mind, if the stone is analysed and shows reflections in different colours, it is best to be on the lookout;

Don’t forget that original gemstones have a high degree of refraction. This means that, in front of a good light source, they reflect an intense and unique glow, on any side of your gem.

4. Go to a jeweller

.Finally, the most efficient method to identify a real diamond is to take the jewel to a watchmaker. With specific instruments, this professional will be able to notice the imperfections that only a real stone has. Meanwhile, counterfeit versions are usually very well finished, with minimal flaws;

It is worth noting that these imperfections originate from the natural mining process – technically known as inclusions. As a result, by observing them with a proper tool, the watchmaker will be able to tell if the material has spots or slight colour variations.

What are the types of diamond

To know how to identify a real diamond, you need to keep in mind that there are different colours of this gemstone in nature. Most of the time, they come in translucent yellow and white versions, almost colourless;

In any case, the Gemological Institute of America (GIA) has also stipulated certain standards for classifying this material and its shades. The classification starts from the letter D, which stands for colourless, to Z, which pertains to striking toned models;

Technical information about gemstones is always important for those who work in the field of jewellery design, so this article provides information about the 4Cs of diamonds.

The 4 basic classifications of diamond

The diamond has 4 basic characteristics.

More than an investment, a diamond represents an expression of affection and love; its purchase should be a safe and pleasant experience.

With this in mind, the GIA (Gemological Institute of America), developed a diamond grading standard that is the most accepted worldwide and that has changed the way diamonds are marketed.

This system, known as “The 4 Cs” is based on the grading of diamonds with reference to their 4 basic diamond characteristics.

The 4 basic characteristics of the diamond “The 4 Cs”:

  1. Carat (the weight in carats)
  2. Color (its colour)
  3. Clarity (your degree of purity)
  4. Cut (its cut or polish)

By knowing the 4 Cs, you can make a safe purchase based on accurate information and you can more easily compare diamonds offered by various suppliers.

1. First C – Carat (weight)

The carat is a unit of weight measurement that represents 200 milligrams, or 1/5 of a gram. A 1 carat diamond therefore weighs 0.20 grams.

The carat is subdivided into 100 units called POINTS. Thus, a 30-point diamond weighs 0.3 carats.

Considering the same type of cut, for example the “Brilliant”, the greater the weight (carat) the larger the stone. See below:

Diamond weight (carat) and size
Considering the same type of cut, for example the “Brilliant”, the higher the weight (carat) the larger the stone will be.

2. Second C – Colour

To facilitate communication between diamond buyers and sellers, the GIA has created a diamond colour grading standard that starts with the letter D and ends with the letter Z. The less colour a diamond has, the higher the colour.

The less colour a diamond has, the higher it ranks on the scale.

Diamonds with a colour grading between D and F are considered colourless, with D being the grading used for totally colourless diamonds.

As the diamond shows more shades of yellow, it moves down the scale, until it reaches the (letter) R grading.

The price of a diamond decreases the more colour it shows. From the letter S onwards, the diamond is considered “fancy” and graded differently.

Diamond colour grading
Diamond colour grading

ABNT/IBGM uses the following deinition, in Portuguese, to translate the GIA colour scale.

Classification of diamond colours

  • D – Exceptionally extra colourless
  • E – Exceptionally colourless
  • F – Perfectly colourless
  • G – Sharply colourless
  • H – Colourless
  • I – Slightly noticeable colour
  • J – Noticeable colour
  • K – Colour slightly visible
  • L – Visible colour
  • M – N – Slightly pronounced colour
  • O – Z – Accent colour
  • Above Z (Fancy) – Unusual or extraordinary colour

Among the most common shades are: 

  • Yellow diamond – a yellow diamond has nitrogen in its composition. A small percentage of this compound is enough to turn a colourless diamond into a yellowish piece.
  • Orange diamond – a yellow diamond has nitrogen in its composition.
  • Orange diamond – the colourless diamond has a nitrogen concentration.
  • Blue diamond – the blue diamond is formed by the element Boron and can be found in both light and dark versions.
  • Red diamond – the red diamond is the rarest diamond in existence, being found only in Africa, Australia and Brazil. There are also some variations of this colour, such as the pink diamond.

3. Third C – Clarity (degree of purity)

The diamond must sparkle profusely and have an “inner fire” worthy of the most valuable of precious stones.

The diamond’s degree of purity refers to the presence (or absence) of inclusions and blemishes that may diminish its value.

In Brazil these spots and inclusions are also known as “jaça”.

The assessment of diamond purity is done by the professional using a 10X hand magnifier or gemological microscope with a 10X lens.

The amount, size, position and nature of the imperfections (jaggedness) determine the diamond’s purity grade. A diamond graded IF (Internally Flawless) is considered the purest.

ABNT/IBGM uses the following definitions, in Portuguese, to translate the GIA purity scale (see table next page)

Diamond purity grade

  • FLAWLESS (FL) – Internally and externally pure
  •  IF – Internally free of inclusions
  • VVS1 and VVS2 – Very small inclusions or inclusions, very difficult to visualise with a 10x magnifying glass
  • .VS1 and VS2 – Very small inclusions, difficult to visualise with 10x magnifier
  • .SI1 and SI2 – Small inclusions, easy to visualise with the 10x magnifier
  • I1 – Inclusions evident with 10x magnifier
  • I2 – One large inclusion or numerous smaller inclusions, easy to visualise with the naked eye
  • I3 – One large inclusion or numerous smaller inclusions, very easy to visualise with the naked eye


Diamond purity grade
Diamond purity grade

4. Fourth C – Cut (cutting or polishing)

The cut grading of the diamond refers to how the diamond has been cut and polished.

This grading should not be confused with the type of diamond cut (Brilliant, Navette, Oval, etc).

The cut is the most important of the 4 Cs and concerns the quality of its cutting.

A well-made cut guarantees the diamond a brilliance and fire, which makes it stand out from other gems.

The cut consists of two very different parameters: the proportions (angles and heights) and the degree of finish (symmetry and polish), which reflect, above all, the care and experience with which the gem was treated at the time of cutting.

The figure below refers to the “Brilliant” cut, considered ideal. All the angles and proportions have been scientifically defined to ensure the best performance of the light inside the diamond and its return to the eyes of the observer, creating the colours and brilliance one sees in a high quality diamond.

Diamond polishing or cutting

  • Excellent – Excellent cut
  • Very Good – Very Good Cut
  • Good – Good Cut
  • Fair – Acceptable Lapidation
  • Poor – Poor Lapidation
Cut or Lapidation on Diamond
Cut or Lapidation on Diamond

The better the cut, polish, symmetry and polish of the diamond, the better the light return and in turn, the higher its value.

ABNT/IBGM uses the following definitions, in Portuguese, to translate the GIA cut scale.

Return of light in diamond 

  • Excellent – Excellent cut
  • Very Good – Very Good cut
  • Good – Good Lapidation
  • Fair – Acceptable Lapidation
  • Poor – Poor Lapidation

.Types of Diamond Cutting

Types of Diamond Cutting

Comments are closed.

Hide picture