Royal Coster
Diamonds Size

MM / INCH (Circumference)

48 / 1.89

49 / 1.93

50 / 1.97

51 / 2.01

52 / 2.05

53 / 2.09

54 / 2.13

55 / 2.17

56 / 2.20

57 / 2.24

58 / 2.28

59 / 2.31

60 / 2.36

Discover your ring size

Measure an existing ring

Measure your finger

1. Download the pdf document below, set it to 100% and print it on A4 paper. You can measure the 5cm line to check the accuracy of the printed dimensions.

2. Check which circle matches the size of your ring. Make sure that the black circle is only visible within the ring.

3. If the ring is in between two circles (sizes), we recommend the larger size.

1. Download the pdf document below, set it to 100% and print it on A4 paper. You can measure the 5cm line to check the accuracy of the printed dimensions. Then, cut out the Finger Sizer.

2. Cut the small gold line. Wrap the sizer around the largest part of your finger and make sure it is tightened.

3. Read your ring size from the sizer. If your ring size is in between two circles (sizes), we recommend the larger size.

Home / Customer Service / Our VIP Service

Our VIP Service

Our diamond consultants are highly trained and experienced experts in the field of diamond jewelry. This goes beyond "trends" or "style". But means we can give honest and sound advice which diamond fits which occasion.

Largest collection of unset diamonds in Europe

The consultants have access to the largest collection of unset diamonds in Europe. If you are looking for a large or unique diamond, we probably have it in stock right here. Our country managers can deliver it directly to you wherever you are in the world.

Discreet and personal

We have several V.I.P rooms available with their own discreet entry. We have welcomed many VIP’s here and although we are very proud of their ongoing business we will never disclose who they are unless explicitly discussed otherwise.

One-stop shopping

Because we are a diamond polishing factory we are a one-stop shopping location. From rough diamond to crown jewel; Royal Coster offers everything discretely and efficiently.

A Royal treatment

Looking to purchase diamonds in Amsterdam? Contact our diamond consultants and we will arrange for limousine service from the airport. Our personal consultants can arrange for everything else you might need, while staying in Amsterdam, as well.

couple toasting in private showroom with diamond consultant

Our country managers speak your language

Besides our diamond consultants, we have country managers available 24/7 for each part of the world. They can come to you and show you our diamond jewelry or help you select the perfect piece for any occasion. Contact us to learn more and experience The Royal service we have been known for by our clients for more than 180 years.

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