Becoming a Polished Diamond Grader in Antwerp

News and Events

Banks Lyon Retail Director, Alex Pecko, recently went to Antwerp, where he became a Polished Diamond Grader. The following article is about his fantastic experience in Belgium and was originally published on the Retail Jeweller magazine.


The Belgian city of Antwerp has been considered the diamond trading capital of the world since the 15th century, when famous Antwerp resident Lodewyk van Bercken revolutionised the world of diamond polishing by inventing a new tool called the scaif. This led to the creation of the multifaceted diamond as we know it today.

Covering an area of approximately one square mile and taking up five streets, Antwerp’s Diamond District is unlike any other place in the world, and a pilgrimage destination for a diamond enthusiast like me.

There seemed no better place to embark on a two-week polished diamond grading course than a city with such a strong connection to the world of diamonds – every year, approximately $16bn (£11.96bn) worth of polished diamonds pass through Antwerp’s most famous district.

I chose to study my course with the International Gemological Institute (IGI) because the organisation is not only the oldest in Antwerp, but also the world’s largest independent gemological laboratory. I felt it was the perfect place for me to deepen my knowledge of dealing with diamonds, from purchasing to valuing them.

The IGI was established in 1975, with a strong focus on staying ahead of changes and continually meeting the market’s requirements, which has led the organisation to where it is today.

I was immediately attracted to the IGI’s rich knowledge of diamonds, as well as the institute’s prestige and the fact that all its courses are based on a practical, not a purely theoretical, approach. The course is run by the IGI’s head of education, Jean-Matthieu Mangnay, whom I had the pleasure of meeting prior to embarking on the course.

My first contact with Mangnay was at International Jewellery London (IJL) in September last year, when he outlined the content of the course. I was delighted to learn that we would have access to the institute’s huge catalogue of stones. This would be a very important resource for me, as in my everyday job I am exposed to many stones of varying qualities.

The polished diamond course is aimed at everyone who wants to learn to “identify, grade and price diamonds according to international grading and trading practices”. The expertise to offer accurate and unbiased opinions of diamonds, based on the four Cs (cut, clarity, colour and carat), is needed if you are, or wish to be, a diamond trader, supplier or retailer, as I am.

Even though I have only been working in our wonderful industry for four years, I have already met many peers who have also chosen the IGI to broaden their knowledge, and this was also key for me.

I spent just over two and a half weeks studying at the institute, alongside classmates who came from all over the world and from all walks of life. I not only made friends but also important industry contacts.

A normal day at the institute begins at 9am, with a quick coffee and catch-up with the other students. The mornings are then spent studying theory, with Mangnay lecturing and answering questions.

After a lunch break, we would put our newly-learned theory into practice, using the institute’s catalogue of stones. A nervy walk up to Mangnay’s desk would then lead to him letting us know whether or not he agreed with our observations, and whether our gradient was considered “correct”. This led to embarrassment on my part on more than one occasion…

I immensely enjoyed learning to analyse stones and getting to know whether they were natural diamonds or synthetic, or simulants – this is particularly relevant to my everyday role. It’s a key skill in my line of work as I need to be completely confident of what I am buying, selling and appraising.

As part of the two-week intensive course, we were given the opportunity to visit a traditional diamond polisher that still operates in the district, and even had the opportunity to polish a diamond in its workshop for ourselves. Mangnay also took us into two of the diamond bourses in Antwerp, where polished diamonds change hands.

The course concluded on the final Friday with a full day of examinations, which consisted of grading a minimum of five “unknown” stones in the morning, followed by a written theoretical paper in the afternoon. Everyone is keen to pass, so the final few evenings were spent studying into the early hours and were somewhat reminiscent of the coffee-fuelled all-nighters of my university days.

Needless to say, during my stay, it wasn’t all work and no play – at night I explored the diverse city of Antwerp. This city is brimming with gems, and not just diamonds – the architecture is truly impressive, ranging from ultra-modern buildings to Gothic landmarks. The food in the many pubs and restaurants is absolutely delicious (after all, this region is well-known for its frites), and the sheer variety of Belgian beer is spectacular, with Bier Central alone boasting more than 300 varieties.

Whether I was studying the theoretical side of polished diamonds, peering at stones through my loupe or walking around the city, I found Antwerp truly unforgettable.

It’s all about trust. In today’s world, especially as an independent jeweller, it’s crucial not to underestimate how much our customers need to trust that we know what we are doing, that we are educated in our field and that we possess the necessary expertise.

They want to be confident that they are getting a superior diamond, one that is certified by a reputable laboratory.

A certificate as a polished diamond grader is a great way to affirm this and to offer peace of mind to our clients that we have a deep theoretical knowledge and understanding of diamonds.

Among other skills, this includes being aware of the distinction between a ‘real’ diamond and a synthetic one and being capable of analysing and grading the four Cs independently.

For a retailer or a supplier, this IGI certification can assure their clients that they are making the right purchasing decision. Our customers should not have to worry about the origin of a diamond, or whether they are buying a natural gem. Their only focus should be on the magnificent beauty and exquisite craftsmanship of the diamond, and the jewellery in which it is set.

I believe this IGI certification helps jewellers to feel more confident when discussing diamonds with their clients, offering a high degree of professionalism to a business.

I found the polished diamond grading course to be excellent. It is outstanding in terms of value for money and also in regard to the wonderful content presented by our lecturer. Not only did he have a wide-ranging knowledge of the subject, but he was also incredibly charismatic, fun to be around and attentive to all students – no matter the questions or doubts arose.

From learning theory to more practical and intensive sessions in the lab, IGI courses are valuable to everyone who wants to work in the diamond world. You could be a diamond dealer wanting to learn more about market developments, you may want to start a diamond business, or you could be a private buyer wanting to learn more about purchasing great jewellery at an auction.

As the retail director of an independent jeweller in the northwest of England, this certification is invaluable and integral to my role and to what we do as a business. Opportunities such as this are priceless and seeing it and experiencing it all for myself is something I recommend others do as well.