Diamonds and their value

Diamonds are considered woman’s best friend. They have been used in jewelry for centuries giving glow, elegance and beauty. They are also known for their hardness and durability.

What determines the value of diamonds

Their value is determined by 4C according to the GIA (Gemological Institute of America)

  • Carat
  • Color
  • Cut
  • Clarity

Carat (Weight)

Carat is the international unit for measuring the weight of a diamond. First was adopted in America in 1913. More specifically one carat equals 200mg. In diamonds that have the same specifications (purity, color, cut) as the carat weight increases so does their price.


Color is also a key feature in evaluating the value of a diamond. The more colorless (transparent which looks white) a diamond is the better it is considered. According to the GIA, the color of a diamont is rated on a scale from the letter D (completely colorless) to Z (it is yellow or brown).

D (Exceptional White+)
E (Exceptional White)
F (Rare White+)
G (Rare White)
H (White)


Cut is the most important feature among the 4C of a diamond, as in addition to its shape it affects its glow, flame and sparkle. When we say glow we refer to the brightness that reflects the diamond, while sparkle is the movement of light inside the diamond. Cut is also evaluated based on the accuracy of its critical angles, proportions, symmetry, and luster.

According to GIA, the cut of a diamond can be:

  • Ideal
  • Excellent
  • Very good
  • Good
  • Fair

To evaluate the cut of a diamond GIA examines seven data. Three of them refer to the appearance of the diamond and have to do with glow, flame, brightness and sparkle. The other four evaluate the cutting technique and design and they’ve got to do with durability, symmetry, weight and luster.

Cut techniques

There are two types of modern cut: brilliant cut and step cut. The most common but also the most ideal cutting style is the round brilliant cut as this type of cut highlights the glow of a diamond.

Diamond’s shape:

  • Roud Brilliant Cut
  • Princess
  • Emerald
  • Marquise
  • Oval
  • Heart
  • Pear
  • Radiant
  • Asscher
  • Cushion
  • Baguette
  • Rose cut
  • Trillion


Clarity has to do with the spots that can appear inside a diamond.

Clarity levels:

  • Flawless (FL): No visible enclosed or external flaws after magnifying glass examination.
  • Internally Flawless (IF): There are no visible enclosed flaws but there are some sparse external flaws after examination with a magnifying glass.
  • VVS1 / VVS2 (Very very slightly included): There are very small enclosed flaws which look very difficult with a magnifying glass.
  • VS1 / VS2 (Very slightly included): There are very small enclosed flaws which are difficult to see with a magnifying glass.
  • Si1 / Si2 (Slightly included): There are small enclosed flaws which are easily seen with a magnifying glass.
  • I1 / I2 / I3 (Included): There are enclosed flaws which are visible with unaided eye.

Whatever diamond we choose we must always keep in mind these four basic characteristics in order to make the best possible purchase.