Welcome to Royal Coster Diamonds

The first official diamond trade in Amsterdam took place in 1576. For over four centuries, diamonds have played a crucial role in Amsterdam's history. Since 1840, Royal Coster Diamonds, the world's oldest diamond polishing factory, has been an integral part of this rich heritage. Royal Coster Diamonds gained international acclaim even before its founder, Moses Elias Coster, was chosen to re-polish the Koh-i-Noor diamond for the British Crown Jewels in 1852. This task ensured the company's reputation for exceptional craftsmanship. Nowadays, Royal Coster is renowned not just for working on some of the most famous diamonds, but also the tiniest ones, as recorded in the Guinness Book of World Records. One of our master polishers, Pauline Willemse, set this specific world record in 1994. A trip to Amsterdam isn't complete without visiting Royal Coster Diamonds!

At Royal Coster Diamonds, we take great pride in offering the largest selection of diamonds in Europe - over 10,000 to choose from! Our team of GIA-certified experts meticulously curate our inventory, ensuring that each diamond meets our highest standards. Every diamond in our collection is immediately sent to be certified by the most renowned international certifiers, such as GIA, IGI, and HRD. And our signature cut, the "Royal 201," is a true testament to our exceptional craftsmanship. With its 201 precisely cut facets, the Royal 201 shines brighter than any other diamond. But not just any diamond can become a Royal 201. At Royal Coster Diamonds, we'll guide you through the process of achieving such perfection. Book a free tour to explore the fascinating world of diamonds and learn all there is to know.

One of the aspects that makes Royal Coster so unique is our open diamond workshops, where you can see our skilled artisans at work. We take great pride in our long history and our commitment to closely monitoring the entire process, from the raw diamond to the finished jewelry. We believe that attention to detail is crucial when creating something truly special. Day in and day out, our cutters diligently shape our diamonds into unique and special cuts. Goldsmiths then set the diamonds into high-quality jewelry. Our large stock makes it possible to create your own custom-made jewelry, also known as Coster Creations. That is why we offer an equally wide variety of loose diamonds and golden settings to choose from, allowing you to mix and match. Choose your diamond and setting to create a unique piece in under 30 minutes!

Royal Coster Diamonds is situated in four impressive buildings right at the renowned Museumplein. Our first building is home to our Diamond Factory, where you can witness our skilled polishers and goldsmiths at work. In the second building, you'll find an array of watches from renowned brands like Longines and Hamilton. The third building houses our beautiful Boutique, where you can explore our signature collections and jewelry. The fourth building features the Diamond Museum, where you can delve into the fascinating origins of diamonds and admire the most renowned stones in history.