How old is your fiancée? 20, 30, 50? A diamond can be four billion years old! Buy her a brilliant, buddy. You can actually afford it. That’s what our expert says. Marcin Marcok from MART DIAMONDS sells these goods and encourages people to invest in them, so he probably knows what he’s talking about.

Interview for the LOGO magazine 6/2019. Interviewer: Łukasz Figielski

I have a grand in my bank account, and I want to propose. Can I even think about a diamond?

Always! The prices of cut diamonds start from several hundred zlotys. Sometimes what matters is not the size but… the mere fact. The selection of a diamond as a gift indicates that a man is mature, and he is reaching for something special and beyond the reach of many. Not financially beyond the reach, but mentally.

For this price I could probably have a potato-sized amber or a diamond the size of a grain of sand. Why should I choose a grain of sand?

Amber is fantastic. But diamonds are forever. Just think about it. Something perfect is created several billion years ago, but it looks so imperfect in its natural form. An uncut diamond looks like an ordinary stone. It waits for billions of years for someone to find it and recognise how special it is, which really isn’t easy. But it’s just the beginning. Now the cutter needs to “bring it to life”!

What else, apart from history, is so mesmerising about a diamond?

Its fire. Brilliance that takes your breath away. Extracting it requires a lot of work from the cutter. In the industry we say that the cutter gives part of their soul to it. They need to give a part of themselves for the life that will appear in the stone…

Where can I buy one at a good price? Allegro? A retail chain? Maybe from you?

Surely you can buy it from me. It’s important what you get apart from the stone. In addition to experience, a seller must also have a document certifying that it really is a diamond and indicating its quality. There are countless gemological institutes which assess the stones. The rule of thumb is the more letters in the institute’s abbreviated name the worse the institute is. The GIA (Gemological Institute of America), IGI (International Gemological Institute) or HRD (Hoge Raad voor Diamant, that is the Diamond High Council; the last two institutions are Belgian) guarantee that what you are buying is what you intended to buy. The certificate is not only a document but also an inscription on the girdle [a band that divides the “upper” and the “bottom” part of a diamond – editorial note].

Martin Marcok - How to buy a diamond

I understand the rule. How can I put it into practice?

Remember that there are no discounts for diamonds. If someone offers something for just a fraction of its value, then they want to cheat you. This stone may be marketed illegally. It may be artificial. It may not even be a diamond at all. You can wind up buying glass that is sold as an emerald even from a reputable jeweler. It’s best to meet the seller. See the papers. And just to talk, as everyone needs a different stone. There are no two identical stones, just like there are no two identical people. Say what you expect from it.

I just want to give it to the one!

But is it intended to just stop her from fussing about, or is it a ring that you would only give to her and her alone?

And that's how you add more zeroes to the price...

Not necessarily. Some are looking for a perfectly pure – a really expensive – one, and the color may be “weak”. What I think is that since you see the color on the outside, then an inclusion, that cannot be seen with a naked eye, but lowers the diamond’s price, can be “something special”. Such a stone doesn’t have to be worse.

Inclusion sounds better than a blemish.

Blemishes are on the stone’s surface, whereas inclusions are inside it. Nature creates all kinds of shapes. The layout of other minerals in the diamond and miro-cracks filled with micro dust are visible under the microscope, and they can often surprise. We have seen a unicorn, baseball player, mask…

Great. But it really doesn't matter, my wife wouldn't notice it anyway.

Diamonds are to supposed to give pleasure. A smile. It’s important that you know it

Nicely said, but investment buying is a bit different.

Buying a diamond is always an investment. Or you buy an appropriate stone and then sell it and earn profit. Or you buy it as an investment in yourself. Your happiness.

When I buy gold, I know what it is and where the price comes from. I just need to look at the gold rate.

It’s similar with diamonds. But everyone knows gold – we have experiences from the communist era and the 1990s – whereas things are different with diamonds. You need to see a specialist. The guarantee is their experience and documents confirming the diamond’s quality.

I have a Swiss-franc loan and an insurance-based investment. I'm very gullible.

Every customer is my employer. A boss. I have to choose the best possible stone that they can afford. It doesn’t necessarily have to be a diamond.

Is a brilliant the most labour consuming form of cutting a diamond?

The most ineffective, we lose up to 70% of the base material. Half of the stone is usually gone after cutting.

So, mathematically speaking, every diamond must look the same?

That’s true. But there are other shapes, like heart, princess, marquise, oval or cushion. Most fancy cuts, that is others than a brilliant cut, are also mathematically defined in some way. The point is to make the stone ravishing, and to make its shape possible to assess according to some standard. The quality and proportions of a cut is a crucial feature when assessing the beauty of a diamond.

A cut is part of the 4Cs principle.

Despite the fact that its influence on the price is the lowest, it is the only feature of a diamond that depends on humans.

No doubt that "C" like carat, meaning the weight, has the greatest impact on the price. What is the third "C"?

Colour. It’s the colour of most diamonds that is “colourless”. The scale begins with D like diamond, and ends with Z. The closer to Z the less beautiful and more brown-yellowish the diamond and the more nitrogen between the carbon atoms.

Another category are exceptionally rare colour diamonds: red, green, blue...

Oh yes, that’s another story. The colour depends on many aspects, sometimes – like in the case of pink or the most expensive red diamonds – on the specific nature of bonds between the carbon atoms. Colour diamonds, apart from red ones, are a great investment.

And the last C?

Clarity, that is pureness. The number of inclusions and scratches is important here. There are perfectly pure diamonds marked as FL (flawless) and IF (internally flawless). There are stones which are so ingrained with inclusions that it is hard to determine their colour (I2-I3/ P2-P3). The evaluation of purity is a task for an experienced grader. We use the services of the GIA institute.

Diamonds are also manufactured synthetically nowadays.

The technique has been known since the middle of the last century, and other gems have been synthesized for even longer. They have become more and more popular in recent years, as they are many times cheaper. But nature will always command a good price. You need to ask yourself whether you can accept the fact that you wear a knockoff  It’s not what others think – it’s about your awareness of having an “original”.