What to Look for When Buying a Diamond


With the right information and specialist advice, buying a diamond should be an exciting and enjoyable experience. During the process it is important to consider the 4 C’s, which are the carat weight of the diamond, colourclarity and cut. These are explained in more detail below…



Carat Weight

The carat weight should be considered along with the spread of the diamond. Two diamonds of the same carat weight may appear visually different in size due to the general proportions of the stone. For example, a well-proportioned 0.50ct diamond should have a diameter of approximately 5mm. In addition, it is important to note that diamond prices jump at the full carat and half carat intervals. A 1.01ct diamond will cost more per carat than a 0.97ct stone, if all the other factors are equal.


7.97 carat diamond



Colour is also an important consideration. Colour grades are assessed as D to Z. D colour diamonds are colourless and attract the highest prices. Diamonds with a grade of M - Z are considered tinted and will display an obvious yellow hue. The colour that you choose may be dictated by your budget but if you are looking for a fairly good colour without premium prices, consider grades G to J. These grades are near-colourless with tints that are difficult for the untrained eye to spot.


It is also worth noting that round and square-shape diamonds often mask colour, where pear, marquise and rectangular-shapes accentuate colour. Higher colour grades for the latter may be advisable.


D colour diamond



Clarity refers to the nature of the inclusions and blemishes. At the top of the scale are flawless diamonds. These are extremely rare and attract premium prices. It is advisable to buy the best clarity grade that you can afford, but it is also useful to note that many inclusions cannot be seen with the unaided eye. For example, SI graded diamonds have noticeable inclusions under a 10x lens, but cannot be seen with the unaided eye. With this in mind, you may be able to choose a lower clarity grade to suit your budget, without compromising on the general appearance of the stone.


If you are looking to buy a rectangular-shape diamond, it is advisable to choose a higher grade as the inclusions are more noticeable in this style of cut.




The cut not only includes the shape of the diamond, but also dictates the overall appearance. The modern round brilliant-cut is one of the most popular cuts today due to its display of brilliance and fire when cut to optimum proportions. If a brilliant-cut diamond is well cut it will appear bright and lively, but when poorly cut, the beauty of the diamond will be significantly diminished. A well-proportioned stone will attract a higher purchase price, but it’s worth every penny.


If you would like something a bit different, why not consider a pear-shape, marquise-cut or rectangular-shape diamond. All have their own merit for beauty and look fantastic in the right setting.

If you are considering purchasing a diamond why not start at Fellows. Our website allows you to view our forthcoming sales, where you can search for diamonds and use the estimate filter to tailor the results to your price range. For advice and guidance on choosing your diamond please telephone or contact us by email.