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The 4 C's to Consider When Buying a Diamond Ring


When shopping for a diamond ring, it's important to be aware of what factors you should consider before you make your choice. At Sonny's, our team of specialists are always happy to help you through this process when you walk through our doors, but we've also put together this online guide to further guide you.

Every diamond is unique, but in order to assess a diamond's quality and rarity, jewellery professionals must be able to compare one diamond to another. This is done using the grading system developed by the Gemological Institute of America (GIA) in the 1950s, which is now the industry's most widely accepted system of diamond grading, worldwide. The GIA system established the use of four important factors to describe and classify diamonds: Carat Weight, Colour, Clarity and Cut.

    Following the guidelines of these 4 C’s will help you to select a diamond that radiates with fire and brilliance.

     1. Carat Weight 

    A diamond's weight is measured in 'carats,’ and one metric carat is equal to 200 milligrams. Put simply, the higher the carat weight, the heavier the diamond.

    Carat weight should not be confused for the size of the diamond, as diamond size can vary depending on the cut.

    Diamond Carat Size Guide
     The carat weight of a round brilliant diamond and its approximate size in millimetres. 


    2. Colour 

    For diamonds, 'colour' actually means lack of colour. Because many diamonds in nature can have a slight yellow tint, diamonds that are colourless or close to it are quite rare. Therefore, the clearer or more colourless a diamond is, the higher its value.

    The GIA's colour grading scale categorises a diamond's colour on a scale from letters D - Z.


    Diamond Colour


    D is the best quality, and diamonds yellow in colour as you go further along the scale. Colourless or clear white diamonds are more desirable because they allow the most refraction of light or sparkle. Brown or yellow-hued diamonds at the Z end of the spectrum are deemed the lowest quality in terms of colour. 

    'Fancy diamonds' are diamonds that exhibit other colours which are not on the D- Z scale, including diamonds with a yellow intensity beyond Z. These diamonds come in tones of naturally saturated reds, pinks, blues, and greens, and are the rarest and most valuable.

    At Sonny's Jewellers, our stock predominantly consists of diamonds within the D-H range. However, we are happy to source and design jewellery containing diamonds of any colour, within the D-Z scale, and beyond.

    3. Clarity

    The organic process through which diamonds are formed means that small crystals can be trapped within a diamond while it's forming. This then causes the diamond to contain tiny flaws.

    Internal flaws in a diamond are referred to as inclusions, while external flaws are called blemishes. The size, position and visibility of these flaws can have a significant impact on diamond clarity.

    Clarity refers to the purity of a diamond measured by the presence (or absence) of these inclusions and blemishes within the stone. Diamond clarity is graded by the visibility of these inclusions under 10-power magnification.

    Our jewellers and gemologists use a scale developed by the GIA which ranges from from FL, which indicates a flawless diamond, to I, which indicates a number of more significant inclusions and blemishes, with number gradations for each category, to rate clarity.

     Diamond clarity guide


    A diamond with poor clarity will have multiple inclusions and external blemishes, which will affect the way the diamond reflects light and as a result, affect the diamond's sparkle.

    The higher a diamond's clarity score, the fewer imperfections the diamond has.

    4. Cut 

    Diamond cut refers to how well a diamond is cut and polished, and diamond cutting is the process of turning the original rough stone into a faceted one. The best diamond cut is perfectly proportioned, symmetrical, and beautifully polished so that the highest amount of light can enter and reflect out of the stone.

    Rough Diamond

    A rough, uncut diamond.



    A well-cut diamond will appear sparkly and bright, while a poorly cut diamond will appear dull and lack-lustre. 

    The higher the cut quality, the more fire and scintillation your diamond will have.

    As a result, a larger diamond with a higher colour score that is poorly cut can potentially be less valuable than a smaller diamond with a lower colour score that is well-cut.

    At Sonny's Jewellers, every diamond is put through our rigorous multi-step Quality Check process. Only once our production experts and award-winning team have examined each ring and are satisfied with its perfection are we happy to allow it to be sold. This precision and attention to detail is what sets Sonny's apart.

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