Benjamin Marriott

Partner in International Diamond Counsellor

The Price of Diamonds

Does anyone in our industry actually know the price of a rough diamond? Nowadays, precious few of us do. But paying the right price for rough is fundamental to our industry’s economics: pay too much or too little, and eventually, we all suffer.

However, very few buyers know the accurate price of rough diamonds. The vast majority of buyers – be they rough diamond dealers or manufacturers – operate on a “guesstimation” basis. People don’t buy rough anymore; they buy futures in polished, guessing what the polished will be worth three months later. The need to keep their factories running is why manufacturers keep buying rough, only to realize those three months later that their projected, or “guesstimated,” profits on the polished goods produced have evaporated.

As independent diamond valuators who have worked for decades in most diamond-producing countries on the African continent and elsewhere, my brother Luke and I have come to realize that the art of buying and trading rough on-site is fading, and, consequently, our role may soon become obsolete.

Why is this so? There are various reasons, among them:
Many of our colleagues in diamond-producing nations no longer want or need foreigners coming in to tell them how to value their diamonds.
In addition, in the current social, post-pandemic climate, concomitant air travel seems less and less appropriate. It’s also become very expensive to have teams of buyers flying between Surat, Antwerp, Dubai, Tel Aviv, Luanda, and Gaborone.

During the Covid-19 pandemic and its lockdowns, we understood that the whole system needed shaking up. We created the technology that now allows us to take rough diamond evaluation and pricing online. The result is a program called eValuer.

Our chief aim in creating eValuer was to take the guesswork out of rough diamond pricing and replace it with data-driven, factual figures. Therefore, our data collection processes involve attendance at and reporting on all major rough diamond tenders and auctions and the valuation of contract rough goods from primary sources – such as De Beers – where the price of those goods is documented and verifiable. eValuer’s prices are up-to-date and based on some US$1.5 billion of rough sales. eValuer is currently used to value and sell over US$2 billion of goods in eight countries. eValuer reports the price paid for rough, detailed into 2,500 price points. This also enables us to produce a monthly rough diamond price index.
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