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Great publication in magazine “Edelmetaal”

June 26, 2017/ BY Alina

June, 2017. In the diamond edition of the magazine Edelmetaal (precious metal) of the Dutch Federation Gold and Silver, an interview with the oldest diamond polishing factory is a real must. Marketing director Ronald Koster explains why guests from all over the world are eager to visit Royal Coster for their diamonds.

Ronald Koster and the Koh-I-Noor diamond in crown jewels

Wide choice of diamonds with the true Coster experience

There are many reasons why guests choose Royal Coster Diamonds. A few of those are the historic location and diamond artifacts. For example, Coster polished the main diamond of the English Crown Jewels (the Koh-I-Noor) and she is Court supplier of the Dutch royal family. Besides this, Royal Coster provides an educational program with a guided tour through the diamond polishing factory where guests learn everything about diamonds. The guides giving the tours speak no less than 27 languages. In addition are all diamonds certified and of impeccable quality. The combination of this is known worldwide as the Coster experience. Ronald: “Our strength is that we can show a lot of diamonds. With all due respect for jewelry stores, but they can’t offer this many diamonds. This wide range of diamonds is an aspect of our business model. The other aspect is that we sell diamonds and yet are not a jeweler, but part of a tourism Amsterdam business model.” We value diamonds by means of the 4 C’s. You will also learn that during our free tour. The 4 C’s are carat, color, cut and clarity. We also focus on confidence: that’s the fifth C. We inform our customers in an honest way so they know how to buy their diamonds. It’s great to be able to do so.

Frank van Poorten and diamond polishing machine

Grinding a diamond is mainly fingerspitzengefühl

Diamond grinder Frank van Poorten shows to the author of Edelmetaal what polishing a diamond all is about. He tells and shows how he can transform a rough stone into the world’s most sparkling diamonds. “What you need is knowledge and experience, but especially fingerspitzengefühl. Everyone can divide a diamond into 57 squares. However, at the moment you deviate from the ideal situation, you need insight and sense of quality. Only then will you show craftsmanship. Grinding is a long process and in it, patience is your most important feature.”

Free tour and the Coster experience

Are you curious about the Coster experience? Book a free tour through our diamond polishing factory and let yourself be amazed by the magical world of diamonds.

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