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Find Your Ring Size

Royal Coster
Diamonds Size
Internal Diameter / Circumference (mm)​
14,01
14,33
14,65
14,97
15,21
15,61
15,92
16,24
16,56
16,88
17,20
17,52
17,83
18,15
18,47
18,79
19,11

How To Measure

The Hands-on Method​ Measure an Existing Ring
  • 1. Grab a tape measure, length of string or strip of paper.
  • 2. 2. Wrap one of these objects around your finger. Mark the place where the two end of the measuring object come together.
  • 3. When using string or paper grab a ruler. Lay it on a flat surface and measure to where the marked point is.
  • 4. Use the chart presented above to acquire the correct ring size.

The Royal Coster Diamonds Give Away

HAVE A CHANCE TO WIN A DIAMOND

Want to win a diamond? In the spirit of Valentine's Day, we are giving away a brilliant cut diamond of 0.30 carat worth €900

Participate in the give away and have a chance at winning. In addition, the lucky winner can choose from a complementary ring or pendant setting and can watch our goldsmiths create your beautiful piece of jewelry.

Join the give away below for the ultimate Valentine's Day gift!

Give-Away Terms and Conditions

  • The diamond give-away (hereinafter referred to as the “Give-Away”) is open only to individuals who are 18 years of age or older.
  • No purchase or payment is necessary to enter or to win the Give-Away.
  • The Give-Away begins on the date of announcement and ends at 12:00 pm CET on February 3rd 2023.
  • The winner of the Give-Away will be chosen at random.
  • The winner will be notified via email within 48 hours of the closing of the Give-Away.
  • The winner must respond within 48 hours of being notified of their win. If the winner does not respond within 48 hours, they will forfeit their prize and a new winner will be chosen.
  • The prize is non-transferable, non-exchangeable and no cash alternative will be offered.
  • The winner may be required to provide proof of identity and age.
  • The Give-Away is subject to Dutch law and is void where prohibited.
  • The decision of the Give-Away organizer is final and no correspondence will be entered into.
  • By participating in the Give-Away, entrants agree to be bound by these terms and conditions.