An Ultimate Guide on Diamond Grading

Comprehensive guide to Diamond grading

Diamond grading courses allow you to gain an in-depth understanding of diamonds and identify the quality of the diamonds. JK Diamonds Institutes offers a fast-paced diamond grading course in both- Rough and Polished Diamonds. 

You could be an absolute beginner in this field. The course provides assistance and transforms students into experts. To get a brief understanding of diamond grading, continue reading!

Diamond grading courses allow you to gain an in-depth understanding of diamonds and identify the quality of the diamonds. JK Diamonds Institutes offers a fast-paced diamond grading course in both- Rough and Polished Diamonds. 

You could be an absolute beginner in this field. The course provides assistance and transforms students into experts. To get a brief understanding of diamond grading, continue reading!


The Indian diamond industry is a product of perseverance. 

Post-independence too, the Indian economy continued to be depressed for years. However, with the expansion of trade and commerce that came in as a result of new policies and amends, the journey towards progress began even for the Indian diamond industry.  

From around the 4th century BC, this country has been associated with diamonds. Today, India is the world’s largest center for cut and polished diamonds. Being well supported by government schemes and policies, the industry is flourishing. 

India is deemed to be the hub of the global jewelry market because of its low costs and availability of highly skilled and experienced labor. India proudly stands as the largest exporter of diamonds in the world. The economy of this country has been blessed with the diamond, gems, and jewelry sector which contributes around 7% to the country’s GDP and 15% to India’s total merchandise exports.

 In 2019, India’s diamond export industry amounted to a total value of 21.9 billion USD, compared to the 17.7 billion USD exported by the United States, ranked second. 

Pandemic situation:

A disruption occurred in the diamond, gems & jewelry industry when the wave of COVID-19 attacked the whole world. Just like the other industries, the diamond industry too began pushing its boundaries of resilience. Everyone had to adapt to the “new normal” including miners, manufacturers, wholesalers, and retailers of the industry. Amid the pandemic, resuming manufacturing operations and trade was daunting. 

However, members of the industry started the units after reframing new rules and different social norms. With new opportunities and adapting to a different path, miners, manufacturers, and jewelers have resumed their business. 

No challenge can stop us from rising higher!

Scope of the diamond industry in India:

The gems and jewelry industry in India are growing rapidly. The diamond industry plays a significant role in India’s economic growth. Surat, a city in Gujarat, is well-known for its Diamond manufacturing whereas Mumbai . is at the forefront of trade and business in this industry.

Presently, India exports 95% of the world’s diamonds as per the stats released by the Gems and Jewellery Export Promotion Council. Aren’t these exceptional stats?

The city of Surat is the largest diamond processing center in and around the city with around 10,000 diamond units. With high standards and constant technological advancements, along with highly skilled manpower and strong government support, this industry is likely to skyrocket in the years to come.

The nature of the diamond industry is global since diamonds are mined in countries like Africa, Australia, Canada, and Russia while trading happens in Belgium and processing of diamonds takes place largely in India and Israel. These diamonds are sold all across the world and the demand for this gemstone is ever increasing. Such factors open up new opportunities and doors for those seeking a rewarding career in the diamond market.

The diamond grading course is technical and the study requires a tremendous amount of precision and practical training to get accurate results. This is why it is of utmost importance to be professionally trained in this technique. At J K Diamonds Institute, a pioneer in diamond, gems & jewelry education, 100% practical training is provided through expert training and individual attention. Studying the current situation and demand for gems and jewelry, there is good room for existing as well as new entrepreneurs to join the industry.

Colin Shah, the Chairman at the Gems & Jewellery Export Promotion Council (GJEPC) expressed optimism saying, “Demand has revived, and the trade is getting good orders from the US, China, Gulf countries, and some parts of Europe. There is good demand in India too. The worst is behind us hopefully. The workers are also returning to join their work as well.”

Well, the future looks bright!

And if you are a beginner, interested in getting a basic understanding of diamond grading- you’re at the right place! Let’s help you understand:

What is Diamond grading?

Professionals who study diamonds use the grading system developed by GIA in the 1950s. They established the use of 4 important factors to describe and classify the quality of diamonds. These are known as the 4Cs: Clarity, Colour, Cut, and Carat. 

But are these 4C’s enough to study and understand the practical diamond market, the quality and the valuation of a diamond? 

Keep reading to find out.

So here’s what the 4C’s mean:


Diamonds come in various shapes and sizes, forms, and colors. Since they are formed under immense pressure and enormous heat, under the surface of the earth, diamonds are bound to have imperfections. These flaws, however, are termed as “internal characteristics” by gemologists. 

The character of a natural diamond is defined by its imperfections. In any case, the beauty of a diamond isn’t compromised in the presence of inclusions. What are inclusions? Inclusions are the internal defects, while the surface flaws are known as blemishes or external defects

Noteworthy fact- Diamonds that have fewer and smaller inclusions or blemishes get rewarded with the highest clarity grades- and higher price tags to reflect that. Diamond clarity is the assessment of imperfections that are present on the surface and within the diamond. 

Diamonds too aren’t perfect, they’re unique with their distinct characteristics.

Diamond Clarity Scale:

I2, I3 Heavily Included Diamonds: These may have more obvious inclusions at 10x and may be visible to the naked eye.

I1 Included Diamonds: These diamonds have minor inclusions that may be visible to the naked eye.

SI Slightly Included Diamonds: 30% of diamond customers buy SI diamonds. Inclusions are noticeable at 10x magnification with SI diamonds. 

VS Very Slightly Included Diamonds: These VS diamonds have minor inclusions that cannot be seen without 10x magnification. 43% of customers buy VS diamonds. VS1 is a higher clarity grade than VS2, which may have some visible inclusions. A VS-grade diamond is less expensive than a VVS diamond. 

VVS Very Very Slightly Included Diamonds: VVS diamonds have minuscule inclusions. Even trained eyes cannot see these under 10x magnification. A VVS diamond is an excellent quality diamond and clarity grade. 21% of customers buy VVS diamonds.

However, the clarity grades mentioned here are not the exact basis in which the diamond trade functions. The diamond trade across the world has localised the clarity grades. For example, Rapnet, a US based aggregator of diamond dealers lists the prices of a new SI3 as well as I4 clarity grades. In India, there are 5 more grades beyond I3 which are considered whereas the 4Cs are restricted to just I3. 

These add to the complexities towards determining the price of the diamonds and it is pertinent to understand these concepts and to be able to value all different graded diamonds based on market forces. J K Diamonds Institute has introduced diamond grading standards that are nearly double the international standards. This simplified approach helps in identifying grades and inclusions in the smallest of diamonds as well. 


“The bigger, the better.” THAT’S NOT TRUE.

The term carat refers to the weight of the diamond, and not its size. Most people believe that a diamond with a larger carat weight is better than the one with smaller carat weight. The carat weight of a diamond is never related to how bright it sparkles. The beauty of a diamond and its sparkle lies in the Cut of the diamond.

As one might expect, as the carats, or weight, of diamond increases, so does the price. The larger the carat size, the more dramatically the price can increase. This is because it is more difficult to find larger diamonds than smaller ones, and so the larger ones are worth considerably more.

The larger the diamond, the more per carat it costs. In other words, the increase in price per carat goes up dramatically for each “magic number.” For example, the difference in price between a 4-ct and a 3-ct diamond greatly exceeds the difference between a 3-ct and a 2-ct diamond.

Things to consider when buying diamonds (Carat Edition):

  1. Worthy buy: Select a carat weight that is below the whole and half-carat marks. For example; instead of a 2.00-carat diamond, put your hands on a 1.90-carat diamond. The difference is negligible in terms of weight but you will end up saving a lot of money. 
  2. Don’t be fooled by the carat weight: The cut adds life to the diamond. This is an important factor because it maximizes the beauty and the sparkle, not the large carat weight.
  3. Fancy shapes cost less per carat: Most fancy shaped diamonds are less expensive compared to an equivalent round brilliant diamond. Moreover, fancy shapes can appear larger than their actual diamond carat weight size, especially when placed in a halo setting.
  4. Choose your diamond based on your ring size: the smaller the finger, the larger the diamond will appear. A 1.50-carat diamond solitaire looks larger on a size 6 finger than a size 8.


The cut is responsible for the sparkle and brilliance of the diamond.

A diamond cut is a guide or a design manual used to give the diamond a symmetry, proportioning and polishing of the diamond. The cut of a diamond greatly affects a diamond’s brilliance; this means if it is cut poorly, it will be less luminous. The cuts lay the ground for the beauty of the diamond and its scintillating shine. For example, what is the ratio of the diamond’s diameter in comparison to its depth? These small, yet essential, factors determine the diamond’s beauty and of course, the price. 

Diamonds sparkle so intensely. They are renowned for their ability to transmit light. A diamond cut is misunderstood as the shape of the diamond. Well, that’s not true. The cut refers to how well a diamond’s facets interact with the light. The magnificence of the diamond is dependent on the skilled and experienced hands of the artists who fashion this stone to the right proportions, symmetry and polish.

To judge the cut grade, without the use of sophisticated and expensive equipment, J K Diamonds Institute for the first time has developed its copyrighted system of OTE and Star effects. These effects can facilitate cut grading of diamonds easily without using expensive instruments. These easy identification methods assist diamond traders practically in the trading process. 

After all, who’s going to carry microscopes and proportion scopes in their pockets while trading diamonds?

Diamond Cuts/Shapes:

The most popular diamond cut is the Round Brilliant cut followed by the Cushion cut. The former has 59 (including girdle and culet) perfectly aligned facets due to which its brilliance really out-shines the others.  You can never really go wrong with a round brilliant diamond which manages to look amazing in every setting; the true classic engagement ring. There are several different shapes that are loved by people. Princess cut, Emerald cut, Marquise cut, Oval shape and Pear shape diamond etc. are some of the most popular diamond cuts available in the market.


When we think of a diamond, we think of a transparent or a colorless gemstone. However, did you know that a colourless diamond is very hard to find? Colourless diamonds are among the rarest and they are highly priced. Most diamonds are found in almost any naturally occurring color, including gray, white, yellow, green, brown, and pink. Red diamonds are known to be the rarest color ever seen in a diamond.

Here’s some General Info About Diamond Color:

  • Part of diamond valuation is determined by the absence of color.
  • Only certified grading professionals should determine a diamond’s color grade.
  • The tone of a ring’s setting can affect the appearance of diamond color.

Diamond color is important:

Most diamonds used in engagement rings are near-colorless with hints of yellow or brown. All things being equal, the more colorless a diamond is, the rarer it is, and this rarity will be reflected in its price. 

In general, the highest quality diamonds are totally colorless, whereas lower quality diamonds can often have a yellowish or brownish tint. Diamond color is measured using the CIBJO color grading standards which goes from D (colorless) all the way to Z (light yellow or brown in color).

Well, now that we’ve understood the globally applicable standard for grading – the 4C’s. Let’s understand if these factors are enough to grade and study the diamonds. 

The answer is no, there’s more to study and understand diamond grading

In the market scenario, the quality, as well as the valuation of diamonds, depend upon factors way beyond the 4Cs. The diamond shapes and facets such as culet, girdle, etc. are all considered in the diamond market as quality parameters which are not taken into consideration by the 4Cs. The demand and supply factors, labor cost, changing and ever-evolving technology, regional differences, etc. all play a part in the determination of the value of a diamond.

Hence, J K Diamonds Institute of Gems & Jewelry has introduced the concept of 7Cs and 7S’ to determine the quality as well as the price of diamonds keeping in mind practical market reality.

If you are a diamond/gemstone enthusiast, and you are motivated to study- apply for the diamond grading course at J K Diamonds Institute.

How does a diamond grading course at J K Diamonds Institute add value to your career?

  • 100% Practical training in assessing diamonds. This course is designed to educate beyond textbooks. The diamond grading course at J K Diamonds Institute has minimal theoretical knowledge because identifying diamonds and their value cannot be a product of written material.. The institution’s infrastructure is well-equipped with high-end technology that assists in identifying and gauging diamond quality. 
  • Apart from lab based knowledge, the institution strives to train students in learning terminologies that are used in the diamond grading industry by experts, professionals and traders. The knowledge of how diamonds are formed, mined, polished, traded, hands-on practical knowledge of domestic markets and their supply chain are provided to the students. 
  • To perform globally, the knowledge of International markets are also covered for loose diamonds and for diamond jewellery too. 
  • Expert professionals impart industry knowledge. The trainers at J K Diamonds Institute have been diamond traders, jewellery manufacturers, and exporters with several decades of experience. Thus, the credibility of this diamond grading course is retained. 
  • Learn using advanced technology. The learning system designed and developed by J K Diamonds Institute in collaboration with Learnathon enables smart learning and enhances student’s learning experiences. 
  • JK Diamonds Institute has introduced a specialised D. Card technique with the highest plotting and mapping of diamonds to successfully identify defects and inclusions easily even in the smallest of the diamonds. This cutting edge and ever evolving technology help the students to grasp better and efficiently. 
  • Network with a strong chain of industry experts. Here, networking is facilitated via Learnathon. J K Diamonds Institute has trained thousands of students over the last 3 decades resulting in a very strong Alumni network across the gems and jewellery industry. The students are able to tap into this database to connect with the right person. Whenever a person needs to look for professional opportunities or business connections, he/she need not wander- the entire network database is made easily available to the students of JK exclusively. This Learnathon app is made available in both Android and iOS systems. 

Seems exciting right? So don’t wait- apply for the diamond grading course NOW!

Diamond Certification

A document that describes the characteristics of the diamond. 

Yes, a diamond certification is very important. Diamond certification is essential for any diamond because it verifies and describes what it is that you’re buying.. Usually, diamond grading certificates are for the end consumer. A diamond certificate includes details like the cut quality, color grade, carat weight and other characteristics. Having proof for what you’re buying is paramount, especially with solitaire diamonds. 

A certified diamond has been evaluated by a third-party lab and comes with a certificate, whereas a non-certified diamond does not. Certified diamonds can be better trusted by end users such as jewelry buyers because they’ve been verified by a professional gemologist. 

However, as a member of the diamond fraternity, you are supposed to rely on your own skills of diamond grading while buying a diamond instead of a diamond certificate. In the business of diamond grading certification, the customers for these labs are diamond traders and jewellers and not the end customers. This can lead to a conflict of interest. 

Hence, several top brands in the diamond and jewellery industry have started issuing their own lab certificates, implying to the customers to trust them as a brand and not any third party certificate. This trend of building a brand is gaining momentum and you should be well equipped and skilled to issue your own lab certificates along with your diamond, gem or jewellery.

Lab grown diamonds

Are lab-grown diamonds/synthetic diamonds fake?

Not at all. 

The only difference between a lab-grown diamond and a natural diamond is their origin. Lab grown diamonds are created using cutting edge technology in a lab. It replicates the natural diamond growing process. 

And what are the results? 

A man-made diamond which is exactly the same as those grown beneath the Earth’s surface- chemically, physically and optically. 

The process of creating shiny diamonds in the lab is pretty interesting. But before we get to that, let’s understand how natural diamonds are formed. Because the processes are highly similar, except that the environment in which they grow differ.  

Diamonds are formed deep deep inside the Earth’s surface somewhere around 1 billion to 3 billion years ago. However, geologists aren’t able to put a finger on the calendar and say this is when these diamonds came into existence. But it is believed that the process started with the burial of carbon approximately 100 miles beneath the surface of the Earth. 

The carbon is exposed to massive amounts of heat. As excessive as 2200 degrees fahrenheit and succumbing to the extreme pressure of around 727000 pounds per square inch. The diamonds are found on the surface of the Earth by means of volcanic explosions. These natural diamonds in their rough state that were buried deep down the Earth’s core are eventually mined by specialised miners.

Lab-created Diamonds.

There are two processes labs use to grow diamonds – High Pressure-High Temperature (HPHT) and Chemical Vapor Deposition (CVD).

HPHT diamonds are made using one of three manufacturing processes: a belt press, the cubic press, and the split-sphere (BARS) press. All of these processes create an environment of extremely high pressure and temperature conducive to diamond growth. 

An HPHT diamond begins as a small diamond seed that is placed into carbon. Using one of the manufacturing processes above, the seed is exposed to temperatures of about 1500 degrees Celsius and pressurized to approximately 1.5 million pounds per square inch. 

The pure carbon melts and starts to form a diamond around the starter seed. It is then carefully cooled to form a pure carbon diamond. 

A CVD diamond begins as a thin slice of diamond seed, which is often an HPHT produced or a natural diamond. The diamond seed is placed in a sealed chamber and heated to around 800 degrees Celsius. 

The chamber is filled with a carbon rich-gas, like Methane, and other gases. The gases are ionized into plasma using technology similar to that of microwaves or lasers. The ionization breaks the molecular bonds in the gases, and the pure carbon adheres to the diamond seed and slowly crystallizes.

Diamond Buying Guide:

  • Go beyond the 4Cs

The diamond may look very beautiful when you see it but if you want to buy a good quality diamond, don’t be deceived by the beauty. Do your homework. Know the 7Cs and 7S’ and gauge the diamond grade and value accordingly.. Check with multiple suppliers on the quality and the price that they are offering. Always check the diamonds yourself and depend on your own skills rather than lab certificates. This will give you an edge and you will never end up paying more than required while purchasing

  • Choose a good jeweller

If you are the end customer, this is for you. A good jeweller is the one who is knowledgeable, well-qualified and armed with the right kind of expert training. He must be willing to answer customer queries and attend to customers professionally. Choose a jeweller who can explain to you the clarity and value of the diamond in simple terms. 

These jewellers will recommend the best buy for you on the basis of your budget. He will guide you based on the trends, your preferences and  also demonstrate the difference between apparently similar stones and diamonds.

  • Ask for a diamond grade report

The diamond grading report is almost a validation of what you are buying. The credibility of your purchase will reflect in the report.. You must note that irrespective of the lab report, you must check on the background and reputation of the jeweller from whom you are going to make the purchase. Consider your past purchases, services, value to the society and their branding. And Insist that any diamond you buy comes with an indisputable verification of its quality.

  • Take care of your diamonds

Once you’ve made a diamond purchase, which by the way is a huge deal- you’ve got to take care of this gemstone. If possible have it appraised and insured. Appraisers and insurers rely on diamond grading standards to accurately evaluate the value of gems.

A simple yet necessary step to take care of your diamonds at home is to keep it clean using soapy water and a soft-bristle brush. 

Remember- Clean your diamonds gently, they’ve already undergone too much pressure!

Learn more about the fascinating world of gems and gemology at JK