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:

Jewellers’ loupe

A jewellers’ loupe is a 10x magnification lens that is used to assess the blemishes, inclusions and tints in the stone that may not be clear to the naked eye. They are easy to find and worth a purchase.

Cut

For many people the cut is the most important thing about a diamond since this is what brings the brilliance by allowing light to enter the diamond and be reflected back. The better the diamond has been cut, the more light is reflected.

A diamond that has been expertly cut should reflect light upwards and make the diamond appear white when viewed from the top. If a diamond appears dark at the centre or the settings are visible through the top of the diamond as shadows these indicate a poor and a bad cut respectively.

Carat

A diamond’s weight is measured in carats or parts of carats. 1 Carat equals 0.20 grammes. A very well cut diamond can appear larger than a badly cut diamond of the same weight. Larger diamonds are much more scarce than smaller ones, so a one-carat may cost £6000 and an identical two-carat diamond may be worth £15,000, all due to rarity.

Pick a band metal

The band for the ring can be made from a variety of metals. Colourless or near-colourless diamonds are highlighted best with white metal. Platinum is also a good hypoallergenic choice for those with sensitive skin. If you want a yellow, white or rose gold band, white metal prongs can still be your setting.

Colour

Colour is graded from D to Z, with D being a rare colourless stone, making it the most sought after. Many of these colour differentiations are so subtle they are unseeable to the untrained eye, but the price of the diamond drops significantly between the two.

Shape

There are e a choice of shapes to choose from for your diamond. The brilliant cut round stone is the most popular. The princess cut is square, creates an illusion of being bigger, and costs less than a round diamond as it is cheaper to create.

Clarity

The clarity rating is based on the flaws in the diamonds, their size, number, location, nature and colour. The relative importance of each flaw is determined so that a value can be calculated.

And Finally…

Research

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.