The 4 C's of Diamonds
The value of a diamond is determined by its Cut, Color, Clarity and Carat, also known as the classic "Four C's". Understanding such criteria as diamond grading reports, and the factors effecting a diamond's cost will help the buyer make a confident and sound decision when making a purchase.
Clarity measures the relative visibility of external blemishes or internal imperfections (inclusions) naturally occurring within a diamond as evaluated by a qualified gemologist. The clarity scale (GIA) is divided into six primary categories.
(F or FL) Flawless
No discernible surface blemishes or inclusions visible when viewed at 10x magnification.
(IF) Nearly Flawless
Insignificant surface blemishes and no internal defects visible at 10x magnification.
(VVS-1 & VVS-2) Very, Very Slight Inclusions
Extremely difficult to very difficult to find surface blemishes or minute inclusions at 10x magnification, but can be more readily seen at 10x once located at 20x magnification.
(VS-1 & VS-2) Very Slight Inclusions
Difficult to somewhat easy to find surface blemishes or minor inclusions at 10x magnification.
(SI-1 & SI-2) Slight Inclusions
Easy to very easy to find surface blemishes or readily noticeable inclusions at 10x magnification, but will usually appear to be "eye clean" without magnification, though some stones will show slight inclusions when viewed from the side against a white background (note: GIA does not recognize an SI-3 clarity grade).
Surface blemishes or obvious inclusions are somewhat difficult to find with the naked eye, but are easy to see especially after being located with 10x.
(I-2, I-3) Imperfect
Surface blemishes or obvious inclusions are somewhat easy, or very easy to find with the naked eye. I-2 inclusions will have an effect on either the diamond's aesthetic appearance (beauty) or durability (potential for cracking), I-3 inclusions will have an effect on both.
Diamond prices increase dramatically as clarity category lines are crossed. SI clarity is generally considered to be the best compromise between cost and appearance, providing excellent value for stones of G-I color and proper proportions (cut). Buyers should exercise caution when making purchases from jewelry merchants who don't know or won't state the clarity of the diamonds offered. Buyers should also be aware that due to the use of smaller diamonds in jewelry pieces, these diamonds are less tightly graded and broader clarity range (two grades, such as SI-1 to SI-2, or I-1 to I-2) specifications are therefore not uncommon.
New laser techniques have made it possible to improve diamond clarity. The process optically eliminates “feathers_, which occur naturally in all diamonds. As a result flaws are less visible and thus improve the stone aesthetically. The diamonds are totally natural and the clarity enhancement is not visible to the naked eye. Only trained jewelers will ever know that you own a clarity enhanced diamond. The effects of the laser treatment are permanent, and the amount of material used to fill the feather is so minute that the Gemological Institute of America (GIA) has reported that the clarity enhancement process ADDS NO WEIGHT to a diamond. Furthermore the GIA confirms that the process is stable under normal wear and tear, and the diamond can be worn as any other diamond.