Diamond cut and shape

The cut of a diamond means both the physical shape of the diamond and the quality of its cut. There are various different diamond shapes to choose between, and which one you select will largely be decided by your personal preference and budget. As a value factor, though, cut refers to a diamond’s proportions, symmetry and polish, which determines how sparkly the diamond is, how well it reflects the light and dazzles onlookers.

Diamond shape

There are many different diamond shapes available. The standard round brilliant is the shape used in most diamond jewellery. All others are known as fancy shapes. Fancy shapes of diamond include Princess cut, Emerald cut, Cushion cut, Heart shape cut, Oval cut, Radiant cut, Pear cut, Asscher cut and Marquise cut. You can read more on diamond shapes here. 

Diamond cut

You want a diamond that shines and sparkles when you hold it to the light – and the quality of the cut will determine the extent to which the diamond scintillates.

In early 2005, the GIA (Gemmological Institute of America) unveiled a diamond cut grading system for standard round brilliants in the D-to-Z colour range. This system, the product of more than 15 years of intensive research and testing, assigns an overall diamond cut grade ranging from Excellent to Poor. The diamond cut grades were developed so that you can be sure of the quality of the diamond you purchase. At diamondport, we only select diamonds with a Very Good or Excellent cut – so you can have complete confidence that you’re buying only the very best diamonds.

The diamond’s proportions (measurements and facet angles), along with polish and symmetry (finish) descriptions, are used to determine its cut grade. Polish and symmetry are also graded on an Excellent to Poor scale. Round brilliant and Fancy cut diamonds are given a polish and symmetry grading. The symmetry of a diamond is important as the more fine cuts a diamond has, the more it reflects the light which is what makes it sparkle. The polish of a diamond is how smooth its surface is, which is also important in how much a diamond will sparkle – the smoother a diamond’s surface, the fewer blemishes it has and the more light it is able to reflect a diamond’s brightness, fire, scintillation (sparkle and pattern), weight ratio, and durability, as well as polish and symmetry, are all considered within this final assessment of cut quality.

Excellent

An Excellent cut graded diamond is one that lets in a great deal of light and reflects almost all of this light, making it truly sparkle. On rare occasions, the levels of light reflection are so great that the cut is upgraded to an Ideal cut.

Very Good

A diamond with a Very Good cut is a great diamond, and will sparkle well. The reduction in price because of the slight reduction in the amount of light reflected represents a diamond that is value for money without sacrificing on quality.

Good

On average a diamond with a Good cut will lose 20% of the light, ensuring it still retains a decent amount of sparkle and presence. Considerably less expensive than diamonds with Very Good or Excellent cut ratings, Good cut diamonds represent a great investment.

Fair

Diamonds with a Fair cut will still sparkle but this fades in comparison with a higher quality cut diamond. This diamond is a good option for the smaller budget as it allows you to buy a loved one a real diamond without breaking the bank.

Poor

A Poor cut diamond is usually cut too deep or too shallow and will not reflect any light as a result. Avoid buying Poor diamonds as they lack the flash of magic and aspiration that diamonds of a higher quality cut possess.