Size and Quality: Why Both are Important for Diamonds

Size and Quality: Why Both are Important for Diamonds

In comparison to engagement ring styles, and working out a budget, deciding on a rock should be simple, right?

With the right guide, we believe so. However, when billions of years go into forming something so beautiful, there are a few things to consider while choosing.


Size is generally measured in carat weight, which is one of the four Cs associated with diamonds, and it’s easy to assume that it’s the most important factor. However, when it comes to finding a diamond you love, it’s not the only aspect in play. In fact, the carat weight should have a strong relationship with the quality of the stone. For example, a large, lower grade diamond is unlikely to look as stunning in an engagement ring than a smaller stone of exceptional quality.


While size is easily defined as carat weight, the quality of a diamond breaks down into different aspects. Here’s where the other 3 Cs come into play.

Loose Diamonds At Passion8

1. Cut

More than any other detail, the cut creates the character of the diamond. Symmetry, the illusion of size, how the stone is proportioned, and the all-important shine, all rely on the quality of the cut. While often confused with shape, the two are actually different. For example, being told a diamond is oval shaped tells you nothing about the quality of the cut, or how it reflects light.

How the diamond interacts with light can be broken down further as well, into three different categories of its own. An excellent cut takes into account each one.

  • Fire – The fire is the sparks of colour seen when light disperses through the diamond. Perhaps best visualised by thinking of Pink Floyd’s album cover for ‘The Dark Side of the Moon‘ , the diamond acts as a prism, breaking light into its different frequencies and producing rainbow flashes for you to admire.
  • Brightness – This is defined as the amount of white light reflected by your diamond, making it shine.
  • Scintillation – Referring to the interplay of the light and dark within your stone, the right balance can make the diamond seem even brighter.

2. Colour

Perfect colour in a diamond is when it’s actually considered colourless, according to the Gemological Institute of America (GIA). The scale they created to rank diamonds for their colour is the one most widely accepted and used, and in it there are 23 different grades, running from D to Z.

From D to F, these diamonds are of the highest colour grade and, unless you’re a trained gemologist, any difference between them is unnoticeable. Due to lacking any visible tint, this grade range matches perfectly with precious metals such as white gold or platinum for engagement rings. A gold band, however, may show through the diamond, adding colour when there is none.

While still of excellent colour quality, the next grade range, when compared to colourless diamonds, might show a touch of warmth to them. Some people prefer this to the coldness of the top range stones, while others may never notice the difference in quality. An excellent cut can also distract from any faint tints present, as the reflected light will draw attention away. Matching these stones to yellow gold bands will neutralise any undertones to the diamond as well, and the stone will look stunning against the rich colour.

Beyond J, the colour tinting the stones steadily becomes more visible and the quality reduces.

Round Solitaire Ring

3. Clarity

Clarity refers to how flawless the diamond is. As with anything natural, it’s rare to find a stone without any faults at all.

Two types of characteristics might mar a diamond – blemishes and inclusions. Blemishes occur on the surface, while inclusions are on the inside of the stone. Sometimes, while a diamond is forming, trapped inside it are tiny crystal molecules which break the uniformity of the stone’s structure.

Many of these flaws are much too small for the naked eye to see, and can in fact be useful as they are like a diamond’s fingerprint, whereas a perfectly flawless stone lacks these identifying features. However, as the clarity quality reduces, the faults can grow large enough to be seen.

How size and quality work together for an engagement ring diamond

While some aspects of a diamond can hold more importance than others, none can be truly sacrificed. In the end, what type of stone you want will depend largely on preference, budget, and ring style.

For example, if you are looking for a solitaire engagement ring, you want a decent sized diamond that doesn’t sacrifice on quality. However, with a halo style ring, the carat of the centre stone doesn’t need to be as large as the surrounding rows will give the illusion of size. Additionally, the tiny diamonds that halo it don’t need to be of the best quality as they will be too small for it to be noticed. 

Some people might love colourless diamonds, but you might discover that you actually prefer a touch of warmth to yours – or, that you’d rather a perfect cut than a slightly larger stone.

At Passion8, we care about crafting exceptional diamonds that you’ll fall in love with. If you need advice for choosing out the perfect one for you, visit your local jewellers for assistance.

Trilogy Diamond Rings At Passion8


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