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Royal Coster
Diamonds Size
MM / INCH (Circumference)
48 / 1.89 48 4½ 8
49 / 1.93 49 9
50 / 1.97 50 K 10
51 / 2.01 51 L 11
52 / 2.05 52 6 12
53 / 2.09 53 13
54 / 2.13 54 14
55 / 2.17 55 O 15
56 / 2.20 56 P 16
57 / 2.24 57 8 17
58 / 2.28 58 18
59 / 2.31 59 R 19
60 / 2.36 60 9 S 20

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The Koh-I-Noor: More than only óur heritage - Royal Coster Diamonds

The Koh-I-Noor: More than only óur heritage

A Royal task

In 1852, Queen Victoria of England was looking for someone to repolish one of her most important diamonds. However, no diamond polisher in all of Great Britain was skilled enough. Experts said a diamond this big would break if people would try to polish it. Nevertheless, the British Royal House wanted the diamond repolished. That’s why they broadened their search. They ended up at an Amsterdam diamond polishing factory, owned by Martin Coster. Martin Coster and his company “Coster Diamonds” already made quite a name for themselves with their incredible craftsmanship. So when the queen asked Coster to repolish the Koh-I-Noor, he was more than happy to accept this royal honor.

To England

Normally, Coster would polish the stones in his own factory in Amsterdam. But a diamond as large as the Koh-I-Noor was very rare, and security was not as advanced as it is now. In other words, it was too dangerous to send the diamond overseas. So for this case, Coster made an exception. Martin sent two of his best master polishers to London: Mr. Levi Benjamin Voorzanger and Mr. Joseph Abraham Fedder. In London, Voorzanger and Fedder installed a steam engine that was similar to the ones they had in Amsterdam. On 16 July 1852, they started their Royal task. After almost two months, they finished on 7 September 1852. From that moment on, the Koh-I-Noor shined more than ever.

Visit from a Legacy

As anyone may understand, we are very proud of this special heritage. Little did we know, there is someone who shares that heritage with us. Last Monday, we got a visit from Ms. Linda Kaye. She told us, she is the great-great-great-granddaughter of Mr. Levi Voorzanger. Linda lives in New York (USA). Through genealogical research, she found Voorzanger’s name. From his name, she discovered his amazing legacy and of course the work he did. She decided to contact us and even come to Amsterdam to see where her great-great-great-grandfather worked. Mr. Levi Voorzanger (left) was a diamond polisher at Coster Diamonds around 1852. Ms. Linda Kaye is his great-great-great-granddaughter (picture: 2019)

Well-preserved history

Director Ronald and polisher Frank gave Ms. Kaye a tour through our diamond polishing factory. Linda saw our in-house polishers working on some sparkling diamonds. Of course, the techniques of diamond polishing are improved over the years. But the core of our craftsmanship is still the same. Our special guest was happily surprised to see we still carry out the job in the same way that made Mr. Voorzanger famous. She saw the replica of the Koh-I-Noor that is in the center of our polishing area. Who would have thought that after 167 years, the great-great-great-granddaughter of the polisher who polished this remarkable stone would visit us? And to see his legacy and the place he used to work.

There is more

But Frank and Ronald had a surprise for Linda. They took her to our diamond museum next door. Among other diamonds, the Diamond Museum Amsterdam also tells the story of the Koh-I-Noor. That story includes some old photographs of the diamond workers who polished it. At the museum is also an antique diamond polishing table. It is identical to the one our diamond polishers worked on in 1852. Of course, Ms. Kaye had to take place behind the table for a moment. You can feel history come alive.

The Royal Legacy

The visit from Ms. Linda Kaye was not only special for her, but also for us. It is inspiring to see that our legacy continues to live on. That our stories and all the diamonds we are so proud of never get lost. It is one of the reasons we introduced our Royal Experience earlier this year. If you want to learn about our rich heritage and the craft of diamond polishing, we highly recommend this tour.
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