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What is the rule of the 4C’s?

Classification of diamonds: what is the rule of the 4C’s?

The 4C’s are criteria that allow gemmologists to evaluate a fine stone or a gemstone for example a diamond. The 4 stands for the number of criteria en the letter C is a reference to the first letter of every criterion. The value and beauty of a precious stone depends primarily on these four criteria.

  • 1.00 carat classic diamond earrings in white gold with six prongs From USD 650
    (excl. VAT)
  • 1.20 carat solitaire diamond ring in white gold with side diamonds From USD 3.610
    (excl. VAT)
  • 0.50 carat solitaire ring (half set) in yellow gold with side diamonds From USD 3.250
    (excl. VAT)
  • 0.50 carat solitaire ring in white gold with princess diamond and side diamonds From USD 2.240
    (excl. VAT)

First criterion: Carat

The unit of measurement for weighing gemstones is the Carat (ct). 1 Carat corresponds to 100 points and 0.2 grams. It’s also very important to know that the size of a diamond doesn’t depend on the number of carats, seeing as they only reflect its weight.  Discovering diamonds of more than 1 carat is very rare. As such, it justifies the higher price range of those diamonds. At BAUNAT, you can find diamond rings set with 0.30, 1.25 and even 3.00ct.

Second criterion: Clarity

One can describe a diamond as ‘pure’, when it has no imperfections inside or out. Only an expert can detect if a diamond is pure, using a magnifying glass that is sufficiently large or a binocular. The latter is a special microscope employed by gemmologists for the analysis of gemstones. With these materials it’s possible to pinpoint the exact location of potential inclusions and to analyse the form, colour and size of the diamond. Diamonds are classified into different levels depending on their purity. Fl of Flawless and IF or Internally Flawless are the highest levels of purity that can be attributed to diamonds of the best quality.

Third criterion: Colour

The colour of a diamond is divided into different categories ranging from D to Z. The more colourless a diamond is, the better the quality. A diamond with a perfectly colourless hue belongs to category D. Diamonds in shades of grey, brown or yellow on the other hand are assigned to level Z. There are also diamonds that exist in ‘fancy’ colours, such as red, green, blue, black or purple, but these are very rare and their value is inferior to a colourless diamond.

Last criterion: Cut

The cut of a diamond can vary from one model to the next. Once cut, the splendour of the diamond gets magnified even more. A cut diamond has many facets, depending on the form. These facets are evenly balanced between the crown and the cutlet of the jewel. They must also be asymmetrical and proportionate to the height of the crown.

Written by: CHLOÉ POUPON-DUMONTET Diamond Jewellery Advisor

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