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
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.

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.

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.

Contributions to the City of Diamonds

Van Moppes Diamonds

Van Moppes Diamonds (est. 1877) was a world-famous diamond-polishing factory in Amsterdam. Together with Coster Diamonds and Gassan Diamonds, they formed the Diamond Foundation Amsterdam to promote ‘the City of...

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A Royal Crest

Recently, Royal Coster Diamonds revealed its crest at its annual Midsummer Night Party. The crest contains various aspects that represent the famous diamond polishing factory. There are two lions, a...

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Starting the Diamond Museum

Royal Coster Diamonds is more than just a diamond polishing factory. In 2007 we opened our own Diamond Museum to share our passion for diamonds with the public. The museum...

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