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In our Education Section we post information and latest news relating to Gems and Jewelry industry in an effort to share our knowledge and information with our valuable visitors. Keep visiting this page for new updates time to time.  

HOW DIAMONDS ARE GRADED?
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Understanding the 4Cs of Diamond Grading

The Gemological Institute of America (GIA) introduced the system of Diamond grading in the 1940s and 1950s, thus creating a common language for understanding the Diamond quality.

This system primarily grades diamonds on the basis of 4Cs, that is Colour, Clarity, Cut and Carat Weight of the stone. Every grading element plays an important role in diamond quality and price evaluation. 

DIAMOND COLOUR:
GIA classifies diamonds as colourless starting from D to Z colour grades, depending upon degree of colour tint present in a diamond. Diamonds colour graded as D are colourless or completely transparent with not tint of any colours like yellow, brown, green etc. Moving downwards on the Colour grading scale, more and more tints of colour gets visible. Typically, the more colourless the diamond is, more valuable it is considered. However, in case of Fancy coloured diamonds like Red, Orange, Blue etc, the estimated prices may be a lot more than a D graded Diamond as Fancy coloured diamonds are even rarer than D coloured Diamonds and can fetch millions of dollars per stone. 

Courtesy: GIA

DIAMOND CLARITY:
The second C of Diamond grading, Clarity is classification of diamonds quality based on the Inclusions or Blemishes present in a Diamond. GIA's Clarity grading scale starts from Flawless to Included. Flawless graded diamonds, as the name suggests, are free from any kind of inclusion or surface blemishes. The flawless diamonds are very rare and and rank as most expensive in Rapaport  or other Internationally accepted Price analysis, along with the top Colour grade D. The scale goes down till the last clarity grade I3, that is, Included 3, which is given to a diamond full of inclusions or blemishes or both.         

Courtesy: GIA

Courtesy: GIA

DIAMOND CUT:
The third C of Diamond grading, CUT classifies the diamond grade based on the polishing, symmetry, position and size of facets in a Diamond. Cut is another contributing factor to the beauty of a Diamond as it determines how much light is reflected back from a Diamond and giving an overall brilliance, fire and scintillation. Diamond Cuts are graded from Excellent to Poor. Without a proper Cut, even top Colour and Clarity graded diamond will appear dull and lifeless. 

Courtesy: GIA

DIAMOND CARAT WEIGHT:
This Fourth Diamond Grading C is the CARAT WEIGHT of a diamond. Diamonds, like all other gemstones are weighed in Carats, which is one-fifth of a gram. There is a straight forward rule for this fourth C, "The larger the better". Larger diamonds, also known as Solitaires, are comparatively much rarer and valued much higher than the smaller ones. Larger diamonds are also the ones which are generally accompanied by a Lab Certificate like GIA, HRD, IGI etc. and often in B2B diamond business, the trading is done based on these Gem lab certificates.    

Courtesy: GIA

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