Marijan Dundek

Diamond consultant

Leading authority on top-quality natural diamonds
16 years’ experience with Graff Diamonds in London
Experienced bidder at Sotheby’s and Christie’s magnificent jewellery and gemstone auctions
Specializing in natural fancy coloured diamonds
Author of best-selling book “Diamonds”

A bespoke consulting service for buying your special diamond

Acquiring a unique natural diamond of the highest quality is a complex and multifaceted process. It requires a unique combination of skills: a trained eye to assess the diamond’s physical properties, specialized knowledge of top-grade diamonds and their potential market value, and a keen understanding of the dynamics and bidders at the leading diamond auctions.

With 20 years’ experience in highend diamond retail, I offer these skills and expertise as a private consultant to both buyers and sellers of exceptional diamonds. I specialize in advising clients who wish to purchase a gem at one of the exclusive auctions of the diamond world.

At the Sotheby’s and Christie’s Magnificent Jewels auctions held twice a year in Geneva, I have helped clients acquire extremely rare and valuable gemstones, including coloured diamonds weighing over 100 carats.

Yellow Diamond

Buying a magnificent jewel

If you are interested in buying an extraordinary diamond at auction, you may be uncertain about the best approach. Take the first step and give me a call, with no obligation. I will talk through with you all aspects of the process and answer any questions you may have, from the quality of the gem to your expectations of the auction.

At the auction, placing a successful bid involves many factors that are only mastered through experience and a specialist’s knowledge.

With the stakes so high, and the bidding moving at a feverish pace, it’s all too easy to get swept up by the competitive spirit and to bid way beyond a diamond’s value - a common trap for the auction novice. My expert guidance, and unflappable ability to keep a cool head under pressure, will strengthen your hand.


As a diamond consultant, I offer the advice and guidance you need when acquiring a top-quality diamond.

If you already have a particular diamond in mind to purchase, I will aim to get it for you at the best possible price. Or, if you would like to source a specific type of jewel, such as a ring or earrings, or a diamond of a certain colour or size, I will help you find the best possible match for your requirements.

Marijan Dundek holding diamond ring

Mr Dundek examines the 18.96-carat Fancy Vivid “Pink Legacy” Diamond ring at Christie’s.

Buying at live auctions

I offer a personalized consulting service that will guide you step by step through the auction process to acquire the diamond of your choice.


I offer advice and guidance in purchasing diamonds from Bond Street jewellers, including Graff, Harry Winston, Moussaieff, Sotheby’s Diamonds and other retailers. My extensive personal contacts and long-established relationships with the most reputable retailers ensure you will get excellent terms for the best quality gems.


If you have an outstanding diamond, piece of jewellery or unique gem that you wish to sell, I can guide you step by step through the process of putting it up for auction at Sotheby’s or Christie’s.

Get in touch at no obligation

For more information on placing your diamond at auction, or to find out how
I can help with your specific requirements, please contact me with no obligation.

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