Our “education” page about diamonds aims to answer all your questions concerning the diamonds. Our goal is to describe the most important characteristics of the diamond which are the 4C.



The carat is the unit of measurement by weight of precious stones. Its origin comes from a tree called the “carob”, whose seeds had the particularity of keeping the same weight over time and were used as unit of measurement in the diamond trade.

The carat of the diamond is proportional to its dimensions.

The important points of the carat:

  • The carat of the diamond represents weight
  • 1 carat represents 0.20 grams
  • Its weight is always indicated until the hundredth (e.g. 1.25 carat)


It must be taken into account that the weight of the diamond is always indicated to the hundredth (ex: 1.23c t). A diamond of 0.998 will be shown as 0.99ct, while a diamond of 0.999ct will be indicated as 1.00 carat on its certificate. A diamond of 0.99 carat does not have the same financial value as the diamond of 1.00 carat whose price will be much higher.

Diamond Size Guide


Born under extreme conditions of heat and pressure in large depths of the Earth, every diamond has its birthmark that makes it unique.

The identity of each stone depends on imperfections embedded inside or outside of it.

First of all in the raw state, every diamond must be cut to make it as pure as possible. Every internal or external inclusion of the stone establishes his identity and precisely defines its final purity to be recorded in its certificate. A certificate being a passport allowing us to recognize undoubtedly the stone among thousands of others.

To determine the purity of a stone we use a magnifying glass of magnification x10. All internal or external inclusions visible under the microscope will enable us to identify and locate with precision every impurity of the stone. The more there are impurities the more they interfere with the trajectory of the light and therefore its brightness.

A diamond with no visible imperfection with a magnifying glass of magnification x10 is called “loupe clean” or “IF internally Flawless.”

Every stone has its visible purity note indicated on its certificate:

F – IF Flawless Internally Flawless
VVS1 – VVS2 Very Very Slight inclusions
VS1 – VS2 Very Slight inclusions
SI1 – SI 2 Slight Inclusions
P1 – P2 Imperfect (inclusions visible to the naked eye)


The color determines the whiteness of a stone. She is compared, with the naked eye, to master stones of several colors, ranging from white to yellow (D-Z).

The more the color of the stone is white (D Colorless) the more its value is important. A stone with a yellow tint will have a financial value that is less than that of a stone without colour.

Of course, this criterion applies only to the white stones and ignores colored diamonds such as yellow, red, pink or blue which the ranking is according to the intensity and beauty of color.

The vast majority of stones that we see in jewelry stores are diamonds of color from D to J.


The look and beauty of a diamond depends more on its size than any other criteria of the 4C. It is one of the most important factors of the 4C since the intensity of the stone’s fire depends on it.

The size of the stone must be extremely precise with symmetry calculated so that light enters the stone from the top (crown) and crosses the stone to finally make it out through the top of all its fire.

The image below shows that a stone which is too flat or too deep will have the effect of bringing light from the top of the stone (crown) and out through the bottom (tail) and will result in a loss of brilliance of the stone.

Independent laboratories (GIA, HRD, IGI, etc.) take into account three distinct parameters to rate the quality of the size:

  • Size
  • Symmetry
  • Polishing

Each of these three criteria is marked by the perfection with which it was executed:

  • Excellent
  • Very Good
  • Good
  • Fair

“Excellent” is the perfect size and “Fair” a bad size.

A diamond is a natural mineral composed of carbon whose internal or external characteristics, are unique. Its weight, cut, clarity and color are the most recognized precepts to reveal its purity. This combination is known as the “4C”.


Each diamond reacts to UV light. This is a reaction by which UV rays, invisible to the naked eye, are transformed into visible light.

Most diamonds have fluorescence which goes from slight to very strong and is of blue color. There are also other fluorescent colors such as green, yellow, orange or color combination.

The effect of fluorescence comes from the reaction between the UV light and the atoms of the diamond, which is caused by the presence of impurity in the structure of the stone.

A diamond having no reaction to UV rays will be marked “None”. This means that there is no reaction between UV rays and the Crystal structure.

Independent laboratories such as GIA or HRD rank fluorescence levels in several categories:

  • None – Nil: No fluorescence
  • Faint: Light fluorescence
  • Medium: Mean fluorescence
  • Strong: Strong fluorescence
  • Very Strong: Very strong fluorescence

It is important to note that a stone showing fluorescence has a financial value that is lower than a stone showing no fluorescence.

Heart & Arrow

The “Heart and Arrows” effect is a visual effect observed in a round brilliant with an almost perfect symmetry, meeting the most stringent standards. Some stones have brilliance and a very pronounced fire and have symmetrical patterns in the shapes of arrows (ring side) and hearts (tail side).

Shape – Form

When choosing your diamond, the choice of shape is one of the most important factors to consider. The shape of the stone and how it is handcrafted has a significant impact on her appearance.

The most famous and most used diamond forms in the jewelry world are in the image below.

Of course, thanks to current technology and laser size, it is possible to carve any stone into the desired shape.


There are several laboratories of stone expertise. The three most recognized and respected in the world are:

  • GIA – Gemological Institute of America
  • HRD – Antwerp World Diamond Center
  • IGI – International Gemological Institute

The purpose of the certificate is to inform the customer of its identification features. The certificate being the report of the classification of the diamond and its quality.

Every certificate give the following information:

  • Certificat Number
  • Shape
  • Measurements
  • Carat
  • Color
  • Clarity
  • Cut
  • Polish
  • Symmetry
  • Fluorescence
  • Clarity Characteristics
  • Comments

It is very important to obtain the certificate of your stone to be certain that you are in possession of a natural diamond and know the true value of your stone.

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