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Jewellery Appraisal In Depth: The “4 Cs” – Diamond Purity and Shape

Wedding Ring Insurance | In the second of a series of articles in which we are looking at jewellery appraisal, and in particular of diamonds, we shall be outlining the final two criteria of the “4 Cs” – specifically Clarity and Cut.


Diamond Purity (Clarity)

Most diamonds have small imperfections called inclusions. The fewer inclusions and the less visible, the higher the degree of purity. The clarity of a diamond is often the least important characteristic of 4 C, as most inclusions are microscopic; They do not affect the beauty of the diamond visibly. To maximize your budget, consider a “pure-to-eye” diamond, rated VS1 or higher, in which inclusions will be invisible to the naked eye.


Classification scale
      • [FL] Flawless: No visible defects, <1% of diamonds. Inclusions are not visible at x10 magnification, the rarest degree of purity.
      • [IF] Without internal fault: Very light defects, <3% of diamonds. The inclusions are so small that they are hardly noticeable at x10 magnification.
      • [VVS1 – VVS2] Very very slightly included: Inclusions are extremely difficult to perceive with x10 magnification. (VVS1: Some tiny inclusions; VVS2: Slightly more tiny inclusions)
      • [VS1 – VS2] Very slightly included: Inclusions are minor and slightly less visible at x10 magnification. (VS1: Hardly perceptible minor inclusions; VS2: Minor inclusions relatively more easily perceivable)
      • [SI1 – Sl2] Slightly included: The inclusions are visible with a magnification x10 and sometimes apparent for a very wise eye. (SI1: Inclusions are sometimes visible with a warning eye without magnification; SI2: Inclusions are usually visible from the breech and often perceptible from the top without magnification.
      • [I1] Included: Diamonds may have more obvious inclusions at x10 magnification and may be visible to the naked eye.
      • [I2-I3] Highly Included: The inclusions are obvious, visible to the naked eye with a magnification x10.
Expert advice

Select a “pure to the eye” diamond, i.e. that has no imperfection that is visible to the naked eye through the crown. Diamonds of this purity are excellent value for money, much cheaper than flawless (FL) diamonds or pure-magnified (IF) diamonds, which are extremely rare and reach much higher prices. If you are interested in a diamond with an SI degree of purity, contact a diamond or jewellery consultant who will examine the diamond to ensure that the imperfections are not visible to the naked eye.


Diamond Shape (Cut)

The Cut is the most important feature of the 4 Cs, as it has the greatest influence on the flicker of a diamond. Even with impeccable purity and colour, a diamond will look dull if its size is of poor quality. When a diamond is cut in the right proportions, the light is reflected from the top of the diamond (which gemologists name the table). If it is cut too shallowly, the light is reflected from below; If it is too deep, the light escapes from the sides.

Set of variously shaped realistic diamonds. Chelsea Wedding Ring Insurance


All forms of diamonds are very different, unique characteristics determine the quality of each shape. Below is a selection of the most popular diamond shapes found on the market.


The round brilliant cut diamond is by far the most popular and sought-after diamond shape today. For almost 100 years, diamond cutters have used complex theories about the behaviour of light, as well as accurate mathematical calculations to optimize fires and shine in a round diamond. Not only is the round shape of the diamond the most sought-after and most sought-after shape but it offers you more flexibility in terms of a balance between size, colour, and Purity while enabling you to get the brightness and shine you desire.


This is our most popular round diamond. Its superb shine and its unique size make it the favorite for engagement rings. The princess shape has sharp corners and is traditionally square. When choosing a colour degree, remember that even if the price of a diamond that is not round J colour is outstanding, the colour may be slightly visible in the corners. And then a princess-sized diamond can vary a lot depending on whether it’s more or less square or rectangular.


What makes this particular shape is its breech, which is trimmed with rectangular facets to create a unique optical appearance. Thanks to its larger open table, this shape brings out the purity of a diamond. If you choose an emerald size with a lower degree of purity, such as SI, do not forget to check the plot on the diamond certificate.


This superb and exceptional shape is almost identical to the emerald size, but it is square. Also, this shape features a breech that is trimmed with rectangular facets in the same style as the emerald waist. If you choose an SI purity, be sure to check the plot on the diamond certificate because this shape brings out the purity of the diamond.


The shape of a marquise diamond can maximize carat weight, allowing you to get a diamond that looks much bigger. This brilliant-cut diamond is beautifully set with round or pear-shaped round stones, and its slender and refined shape will enhance and refine your fingers.


Chelsea Wedding Ring Insurance

Chelsea Insurance Brokers provide a comprehensive insurance provision for astute clientele who wish to protect their possessions and property, yet, lack the moment of time or awareness to hunt for an appropriate insurance company. Their services include international protection for jewellery including timepieces and wedding ring insurance. Get in touch with Chelsea Insurance now and protect your property and possessions using an insurance corporation which is internationally esteemed.