If you’ve done any research into buying a diamond ring, you have probably heard of the 4 C’s – Color, Clarity, Cut and Carat. However, unless you are an experienced jeweler, you may not know how to interpret what those 4 C’s really mean for you.

Use this handy guide to learn more about how diamonds are rated.


GIA Diamond Color Scale


Diamond Color is rated by the GIA D-to-Z scale

Not every diamond is crystal clear – in fact, diamonds without any color are rare and command a much higher price tag.

Diamonds can range from virtually colorless to light yellow or brown. The GIA D-to-Z scale is a great way to consistently categorize a stone’s color. The closer to the beginning of the scale, the clearer the diamond is. In contrast, when a stone is further down the alphabet, it has more color and is less valuable.

According to the GIA, diamonds fall into 5 general color categories:

  • D-F is Colorless
  • G-J is Near-Colorless
  • K-M is Faint
  • N-R is Very Light
  • S-Z is Light


Diamond Clarity Scale

Diamond Clarity Ranges from Flawless to Included

Diamond clarity refers to the inclusions and blemishes that are found in a Diamond. Inclusions are imperfections that can be found inside a diamond at 10x magnification. Blemishes are imperfections that can be found on the outside of the diamond such as nicks and scratches.

The fewer imperfections a diamond has, the rarer and more valuable a diamond is. Stones at the higher end of the scale will not have imperfections that are visible to the naked eye. You may, however, be able to see some visible flaws on a diamond towards the end of the scale.

We again turn to a GIA scale to rate a diamond’s clarity. The nature of a stone’s imperfections will affect where it ends up on the scale. Things like size, number and position of inclusions and blemishes will affect a diamond’s rating.

There are 11 clarity ratings on the GIA Scale

  • Flawless
  • Internally Flawless
  • Very Very Slightly Included (1)
  • Very Very Slightly Included (2)
  • Very Very Slightly Included (3)
  • Very Slightly Included (1)
  • Very Slightly Included (2)
  • Slightly Included (1)
  • Slightly Included (2)
  • Included (1)
  • Included (2)
  • Included (3)


Diamond Quality Guidelines

The Quality of the Cut from Excellent to Poor

It is important that every diamond is cut by someone who knows how to play with the angles of the stone to make it as luminescent and sparkly as possible. Playing with patterns on a stone allows for the three optical effects of a diamond: brightness, fire and scintillation (or sparkle).

Brightness is the flashes of white light that enter and reflect within the diamond. Fire is flecks of color that help make the diamond pop. Scintillation is the play between light and dark areas that make the stone sparkle. Jewelers will cut and polish a stone to play with these three effects beautifully.

It is important to note there is currently only a standard rating system for round diamonds, but the same principles apply to cutting other shapes. The range of cuts on diamonds includes:

  1. Excellent
  2. Very Good
  3. Good
  4. Fair
  5. Poor

What is a Carat?

Diamonds are Weighed to Find the Carat

The carat of a diamond is the most straightforward of the 4 C’s because it is derived by the weight of a stone.

A metric carat is equal to 0.2 grams or .007 ounces. A small paperclip is roughly the weight of one carat.

Diamonds are weighed with extreme precision, going down to a thousandth of a carat. This allows the jeweler to get very specific measurements on the value of the diamond.

There is a lot to consider when purchasing diamonds. A trusted jeweler will be able to help you find the right diamond that fits your needs. If you have any questions about the rating of a diamond, give The Austin Diamond Room a call at 512-458-4367. With over 20 years of experience, we are here to support you for all your jewelry needs.

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