Stones: All About Diamonds

Dream Job – Buying diamonds!

IMG_1841-150The bespoke nature of our jewellery means we can’t just buy off-the-shelf diamonds and precious stones. For each of our hand-made pieces we have to match the perfect stones and to do that – and make sure the diamonds are as good a quality as the rest of the jewellery – we need an expert. Meet Henri Keesje, a fifth-generation diamond merchant who sources all of our diamonds and precious stones.


A real pedigree

Henri 2Based in Antwerp, the centre of Europe’s diamond trade and the largest diamond district in the world, Henri is ideally placed to find us the millimetre-perfect sparkling stones we need for your jewellery.

Henri’s family originally lived in Amsterdam but moved to Antwerp after World War II. His grandfather was a baguette specialist – this shape is commonly used in channel set rings, either as an eternity ring or in the shoulders of other styles.

His father specialises in buying rough diamonds from Africa for the wholesale market, and is still involved with the family business, giving advice and casting a critical eye over stones when needed.

Henri himself is an expert in invisible settings for stones and also in colour-enhanced diamonds, which are created by an electron beam process which treats natural diamonds to change the colour, usually changing them from clear to blue, yellow, pink or even brown.

The process

Henri1Travelling all over the world, Henri spends his time at trade fairs looking for diamonds and precious stones either to add to his stock or for a particular piece of jewellery. We’ve worked with him since 2001 when Henri met Iain at a jewellery fair in London.

When we know we need a particular stone we’ll get in touch with Henri. He will know whether he has options in stock or whether he needs to find stones that fit the brief. We will know the budget and the exact specifications (see our guide on the different ways of grading diamonds ), but can also vary these to make savings or spend more, depending on what the customer prefers.

Sometimes Henri will send us stones on approval – so we get to see and handle the stones before buying them on our clients’ behalf. Other times they are being displayed at international jewel fairs so aren’t available to be seen in advance.

On every occasion we know Henri will find us the perfect stone for the ring, earrings or bracelet we’re designing – the beauty of having an expert in the wider IHD team.

More about the man

Having been around the diamond business since he was a small boy, Henri now works for around 50 customers all over Europe. He has several assistants who help with the administration of the business, allowing him to travel one or two days a week to source the stones his clients need.

“I’ve seen stones worth up to $10m at international fairs,” he admits. “And I have been known to buy stones for up to $1m for my clients.”

We pressed Henri for his views about a favourite cut of diamonds, but he didn’t allow himself to be drawn: “Every diamond has the potential to be beautiful. A well-cut diamond, even if it’s tinted, would have sparkle and reflection that makes it shiny and magic – and easy to fall in love with.”

He did explain that diamond folklore says there’s a cut of stone for every personality – those who like order prefer more square cuts such as princess or emerald; more romantic people go for heart, teardrop or round (brilliant) cut. It’s fair to say we haven’t noticed any strong links between people’s personalities and their precious stone preferences, but he’s the expert!

We wondered whether there was pressure to find his wife just the right diamond when he proposed and asked whether she has a favourite kind of stone. “She just loves great design,” Henri laughed. “Bracelets with lots of stones are a favourite.”

Creating options with diamonds and precious stones

Henri’s speciality in colour-enhanced diamonds has led us to offer these as an option for clients. They can make a real design statement without carrying the high cost of naturally-mined coloured diamonds, which can add several zeros on to a price for similar sized stones.

If you’re interested in colour-enhanced diamonds , do have a chat with us as we can advise on what’s best for the piece of jewellery you have in mind. And of course, if you want to visit us in the studio to talk about your next bespoke jewellery purchase, just give the team a call on 01274 551224.

Everyone talks about the 4c’s (cut, clarity, colour, carat), however, there is a lot more to it that that!


Don’t confuse cut with shape. Shape refers to the outward qualities of the diamonds shape – round, square, pear and emerald. Cut refers to the reflective qualities of the diamond – a good cut makes all the difference to a diamond. The light that should appear to come from the very heart of the diamond and reflect back up to the eye, you don’t want any leaking out!

Selecting the grade of cut is really a matter of preference. To give you an idea (guidelines only):

Ideal Cut – Intended to maximize the brilliance. Rare and fine. So yes, expensive!

Premium – Very similar to the ideal cut but can often be bought for slightly less. But yes, before you ask, still expensive.

Very Good – Reflecting most of the light that enters them a good deal of brilliance is created. With these diamonds, the cutters have chosen to stray slightly from the preferred diamond proportions in order to create a larger diamond.

Good – Diamonds that reflect much of the light that enters them. Their proportions fall outside of the preferred range because the cutter has chosen to create the largest possible diamond from the original rough crystal, rather than cutting extra weight off to create a smaller Premium quality diamond. If you don’t want to sacrifice quality or beauty but do want to stay in budget then this is the cut for you!.

Fair & Poor –  Reflects only a small proportion of the light that enters it. Typically these diamonds have been cut to maximize the carat weight over most other considerations.


Here we are talking about blemishes (on) and inclusions (this is basically the black spots in a diamond) the stone. It should be no surprise that most diamonds have flaws!

F = Flawless – No internal or external flaws. Extremely rare.

IF = Internally Flawless – No internal flaws, but some surface flaws. Very rare.

VVS1-VVS2 = Very Very Slightly Included (two grades) – Minute inclusions very difficult to detect under 10x magnification by a trained gemologist.

VS1-VS2 Very Slightly Included (two grades) – Minute inclusions seen only with difficulty under 10x magnification.

SI1-SI2 = Slightly Included (two grades) – Minute inclusions more easily detected under 10x magnification. These are diamonds which gemologists call “eye-clean” – diamonds with no inclusions visible to the naked eye.


Fact: the whiter a diamond’s colour, the greater its value.

Exception: Coloured diamonds! These diamonds, which are very rare, can be any colour from pink, blue, green and yellow and are actually more expensive. We had some amazing chocolate brown diamonds in a little while ago which we all fell in love with.

Diamond colour grading starts at D and goes through to P. D through F are pure white and the most valuable and desirable because of their rarity. We would recommend if you are wanting white metal then use colours D through to I. If you use colours J and below they tend to be a lot yellower in colour and would be much more noticeable in a white metal.


A carat is a measurement of a diamonds weight not size. It is really important to remember that a larger diamond with poor cut, colour and clarity will appear LESS eye catching than a small diamond with excellent cut, colour and clarity. The symmetry and the top of a stone is also important when looking at bigger stones. Lets give you an example. There are two 1ct diamonds sat next to each other. One of them could have a lot of the weight sat underneath the stone and a small table top and the other stone will have a bigger table top and less weight underneath the stone. The one with the most weight underneath the table top is a less desirable stone as you are unable to see as much of the stone. The stone with the larger table top will probably cost you more but you can see more of the stone and would be a much better investment.


This is the blue print that gives you the exact details of your diamond. It allows you to compare diamonds properly. We would recommend that if you are buying over 1/2ct diamond then you should look at buying one with a certificate. You need to be careful what type of certificate you are buying as with many things in life, some are not worth the paper they are written on.

The top three certificates are GIA, HRD and IGI. If you are getting a certificate from the shop you are buying a diamond from then just be aware that you are putting your trust in them, are they qualified to give you this advice? Trust is very important in the diamond trade so please make sure you can trust the person you are buying them from. If it seems too good to be true then it probably is!

If you need any help or advice then you are more than welcome to pop in to see us so we can answer any questions you may have.


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