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Find Your Ring Size

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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our royal legacy

Royal Coster’s Royal visitors

We always shared a warm relationship with Royals. Not only the Royal House from the Netherlands, but Royal Houses from all over the world. Since our foundation in 1840, a lot of royals traveled to Amsterdam to trust us with their jewelry. They knew that Coster used an innovative way of cutting and polishing diamonds. To this day, our fantastic craftsmanship attracts royals and celebrities from all over the globe.

A special assignment

Normally, people come to us. But for Queen Victoria of England, we gladly made an exception. In 1852, two of our best diamond polishers went to London. They had the task to repolish the world famous Koh-i-Noor diamond. This is one of the most valuable diamonds around and part of the English Crown Jewels. Even today, it is one of the finest examples of craftsmanship in diamond history.

In the second half of the 19th century, the British Royal House wasn’t the only royal name trusting us with their jewelry. Among the royals we welcomed were Napoleon Bonaparte, Prince Victor Emanuel, and Empress Sisi. Our list of famous visitors is long and unique. Especially when you consider that traveling at the time was an expensive luxury. It was done seldom, which makes this royal list even more impressive.

royal experience Royal Coster Diamonds, diamond tour, diamond factory

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