 |
It means that you know exactly what you are buying. Let’s examine the process. First of all, certification (a grading report) is only valuable if it is conducted by an independent, not-for-profit gemological laboratory that specializes in grading diamonds. The two most prominent and respected labs are Gemological Institute of America (GIA) and American Gem Society Laboratory (AGS). Bella Ideale™ Diamonds only sells diamonds that are graded by these respected laboratories, because their standards are rigorous and certified grading reports are accurate and reliable. Secondly, the process involves a very thorough and rigorous examination of all aspects of a diamond’s physical qualities that the industry refers to as the "Four Cs" – Cut, Clarity, Color and Carat (weight).
|
|
|
Finally, each gem is graded by more than one specialist. They then confer to reach agreement. When agreement is reached, a certification document on all Four Cs is issued which should accompany the diamond through the sales process.
Cut
"Cut" means the proportions and finish of a polished diamond. Proportions are the angles and relative measurements of a diamond’s facets and relationships between them. Finish is the quality of the polish and the symmetry of the facets. If one proportion factor is more extreme than the others, a lower grade can be assigned. If the diamond lacks brightness, fire or proper scintillation, a lower grade will be assigned. In the GIA system, cut grades are either "Excellent", "Very Good", "Good", "Fair" or "Poor".
Scintillation is an important indicator of a diamond’s proportions and symmetry. It has two components: sparkle and pattern.
- Sparkle is spots of light that appear when the diamond, the observer or the light source moves.
- Pattern is the relative size, arrangement and contrast of bright and dark areas that result from the polished diamond’s internal and external reflections, when viewed face up.
|
Clarity
“Clarity” is a diamond’s freedom from inclusions and blemishes. Inclusions are inside a diamond or extend from the surface into the diamond. Blemishes are confined to the surface of the gem. The fewer the inclusions and blemishes a diamond has, the higher its grade. Each certification by the GIA will contain a visual plot of the size, number, position, nature and relief of inclusions and blemishes that identify the diamond. This “fingerprint” not only separates this gem from all others, it provides the buyer with a professional analysis of the content of the diamond being considered for purchase.
The GIA diamond grading system divides “Clarity” into the following eleven clarity grades; “Flawless”, “Internally Flawless”, “Very, Very Slightly Included” (VVS1 and VVS2), “Very Slightly Included” (VS1 and VS2), “Slightly Included”(SI1 and SI2 ) and “Included” (I1, I2 and I3).
- The “Flawless” grade is self explanatory and very rare.
- “Internally Flawless” means the diamond is flawless except for blemishes.
- VVS1 and VVS2 means that the inclusions are minute and range from “very, very difficult” to “very difficult” to see by a skilled grader using 10X magnification.
- VS1 and VS2 means inclusions are minor and range from “difficult” to “somewhat easy” for a skilled grader to see using 10X magnification.
- SI1 and SI2 contain noticeable inclusions when viewed by a skilled grader using 10X magnification.
- Inclusions in diamonds with an SI1 grade by the GIA are not generally visible without magnification when viewed face up.
- Diamonds graded SI2 and lower can be visible without magnification and are not sold by Bella Ideale™ Diamonds as center stones. These need to be seen in person and are not suitable for sale on the Internet, in the opinion of Bella Ideale™ Diamonds.
Color
Diamonds fall into a “normal color range” from colorless to light yellow and light brown. (There is also a Fancy Colored Diamond scale, which is outside the normal color range that we will ignore here to avoid confusion.) The normal color range is also referred to as the “D to Z Range “, because of the letter grades that the GIA uses to identify color. “D” is colorless and “Z” is a light yellow or brown, as examples. With all other factors being equal, colorless diamonds are the most valuable. To help discern and communicate color for grading purposes, the GIA has separated color into these 5 ranges.
Carat (Weight)
Diamonds are measured by carat weight. All other factors being the same, the greater the weight, the more valuable the gem. One carat weighs .2 gram. Also, each carat is subdivided into “points”, with 100 points per carat. Diamonds weighing less than one carat are referred to by their number of points. For instance, one-quarter of a carat can also be referred to as 25 points.
Engraving
As a further method of separating diamonds, the grading laboratory may engrave the certification number on the girdle of the diamond. Since the laboratory charges for this service, this engraving is not always present.
Fluorescence
Fluorescence is usually observed by illuminating a diamond with an ultraviolet lamp. The diamond absorbs energy from the lamp and in turn can emit a bluish or greenish color. Since part of normal visible light contains an ultraviolet component, fluorescence can influence the observed color of the diamond. Diamonds that impart very strong fluorescence can have a hazy or milky appearance and can have a lower grade and value. The certification will indicate the amount of fluorescence the diamond emits, if any.
Paul Buchanan
President, Bella Ideale Diamonds
|
