How To Assess a Diamond’s Quality

Shopping for a diamond for the first time makes most of us accept the stone’s worth as told to us by the jeweller. When it comes to a diamond’s attributes, it’s not always easy to understand what an expert means when they talk about a particular diamond. Having some understanding of a diamond’s quality can help you purchase the best value diamond for your investment. Here are some things to know before you go shopping:

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In the diamond trade the 4cs, being the cut, clarity, colour and carat weight of a diamond are used together to describe the quality of each unique diamond. The most important of these four is widely agreed to be the diamond’s cut, since this is what gives the diamond its beauty. A superior cut will raise the perceived condition of the diamond, creating an illusion that it is bigger than it really is and has a better clarity and colour ranking than has been registered by diamond experts or jewellers. The expertise of the cut allows all this to happen because it plays with the reflection and refraction of light.

A colourless diamond plays with the light better than one with a hint of colour. A colourless diamond is rarer than one with a slight tint, which makes it more expensive. The link between rarity and cost applies across all 4Cs.

When there is talk of brilliance and fire, brilliance simply means the colourless light that comes from the stone and fire is the coloured sparkle that you can see when the stone is exposed to light.

One other element which can affect the value of a diamond is fluorescence, which is emitted by diamonds when exposed to ultraviolet radiation such as that found in sunlight and fluorescent lights. A strong blue (the most common) fluorescence can make a light yellow diamond look closer to colourless in sunlight as they are opposite colours and cancel each other out. Tested under ultraviolet light almost one-third of diamonds fluoresce to some degree. Colourless (D-F) diamonds graded with a strong fluorescent lose value as fluorescence can make a stone look defective and cloudy.