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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 2nd C: The Color - Royal Coster Diamonds

The 2nd C: The Color

The color of a diamond –or rather the lack of it – tells us something about the value and quality of the diamond. A diamond that consists of carbon only is pure white. This is the highest quality and the rarest form of a diamond. If the carbon is polluted with for example nitrogen, the diamond will be a yellowish or light brown color. The more a diamond is affected, the lesser bright its color is.

Donny Explains

Our Chief Purchasing Officer helps you to understand the basics of the 4 C’s of diamond valuation. A more detailed explanation, you find below this video.

The color of a diamond

The color of a diamond is determined by using verification stones. These are diamonds in all different colors and gradations. Usually goes: the less color, the more valuable the diamond is. However, it is not like yellow(ish) colors are worthless. An example is a yellow stone that was recently sold at an auction for 8 million euros. Quite something for a polluted stone don’t you think? Below is a scale with the current and old names, that explains how a diamond is graded based on color and the absence of it. The closer to the start of the alphabet, the purer the stone.

diamond colors explained with old and current names

Colored stones

Colorless and yellowish stones are not the only possible colors for a diamond. Diamonds are found in every color imaginable. Something happened to every diamond that is not white or yellow. A blue diamond, for example, is polluted with boron. A green stone has been in contact with radioactive rays during the formation of the diamond and was also exposed to a much higher temperature than it normally would be. Within a red, pink, orange or brown diamond, the crystal lattice has been damaged during the transport from the core to the earth’s crust. The crystal lattice is the way the atoms are connected to each other. When these atoms are shifted, it will damage the lattice. This cause the light to reflect in a different way than it does for regular diamonds.

Blue, green, pink and mainly red diamonds are the rarest colors and are therefore the most valuable diamonds.

colored diamonds in tin can

Learn more about colored diamonds and gemstones

Both colorless and colored diamonds are stunning because of their amazing sparkle. The fairest colored stones and diamonds can be seen during a Royal Experience. Our experienced guides love to tell you everything about the 4 C’s as well.

The other C's:

> The first C, Carat
> The third C, Clarity
> The fourth C, Cut

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