Diamond Grading is a process of recognizing the value of a diamond based on standards provided by GIA. A diamond is provided with a rating from 0 – 10. The best diamond has a rating of 0 and the worst can have 10. Diamonds are rated on 4 Cs which are Color, Clarity, Carat Weight, and Cut Scale. A diamond’s value is often affected by the rareness of one or more of the four Cs.
Cut refers not to a diamond’s shape but to a diamond’s proportions, symmetry, and polish. The beauty of a diamond depends highly on the cut. A cut scale has values distributed in a range from 0-10 which have 0-1 in excellent,2 is very good,3-4 is good,5-7 is fair and 8-10 is poor.
Three optical effects occur in the diamond which shows how the diamond interacts with light and create desirable visual effects: The white light reflected internally and externally from the diamond called brightness, white light scattered into seven colors and making the rainbow which is called fire, and the reflection making pattern of light and dark areas due to which diamond produces sparkle, called scintillation. Approximately, 20% of light reflects off immediately after striking from the surface of the diamond. Of the 80% that enters, a portion will escape through the bottom of the diamond.
Clarity refers to the degree to which small imperfections also known as inclusion are present due to the formation of diamond deep within the earth, under extreme heat and pressure. A clarity scale has values distributed in a range 0-10 which have 0 in flawless(IF),1-2 is very very slightly included(VVS),3-4 is very slightly included(VS),5-7 is slightly included(S) and 8-10 is included(I).
Flawless diamonds are very much rare that it’s possible for a person to spend a lifetime in the jewelry industry without ever seeing one, and they have the highest prices. If you are buying diamonds and cannot tolerate imperfections, even those you cannot see, choose a VVS2(2 on the scale) or better diamond. About 10% of all diamonds sold fall into this category. The most popular range is the VS1-VS2(3-4 on the scale) diamond. These diamonds appear flawless to the naked eye. Almost half of all diamond people purchase fall into this range.
Diamonds are available in a variety of colors. The yellowness of the diamond lowers its prize. A small presence can bring highly change in values of two diamond having the same cut and same clarity.A color scale has values distributed in a range from 0-10 which have 0-1 in colorless,1.5-3 is nearly colorless,3.5-4.5 is faint,5-7 is very light and 7.5-10 is light and after it,it is fancy yellow. Color becomes much harder to detect once a stone is set in a ring which is also having some other colors.
Carot Weight Scale
Diamonds are sold by the carat (unit of weight).the value of carat into grams is,1 carat equals to 0.2 grams.The carat weight ranges from 1-3.As the carat increases,the cost of diamond increases.Because a heavy diamond is rare to find and is too much valuable. The price of a diamond increases exponentially with the carat weight.Two diamonds having equal carat weight can also appear very different in size becaus of difference in the shape of the diamond.
When you are buying a diamond you should focus on cut grade, which is the most important factor in determining the overall appearance of a diamond. Because a diamond having poor cut will seem dull even with excellent clarity and color. While a diamond having proper well cut and having a slightly lower color or clarity will still look quite beautiful, due to its superior ability to create sparkle and brilliance.