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Certified Diamonds Buying Guide : How to Buy Diamonds

April 24, 2018

For most people, buying diamonds for the first time can be a little overwhelming. This is why we want to ensure that your experience be simple, straight forward, delightful and that you are equipped with the right knowledge when choosing a diamond.

Diamonds are graded according to the 4 basic criteria, Cut, Colour, Clarity and Carat. Knowing the 4 C’s will help you choose the perfect diamond and at a price that is comfortable to you.





Of the 4 C’s, Cut is the most important criteria. It determines how sparkling and brilliant a diamond is.

A well cut diamond displays these three characteristic, Brightness (the amount of light reflected from the diamond), Fire (the dispersion of light into rainbow colours as it passes through the diamond) and Scintillation (the flashes of light as you move the diamond, commonly know as “Bling”)

A well cut diamond gives you the maximum return of light as light strikes the diamond. It will sparkle no matter how big or small the diamond, and regardless of its Colour. At Diamondlite, we affectionately call these “Happy Diamonds” as it makes us smile every time we look at it.

A poorly cut diamond however, may be either too shallow or deep. These cuts of diamonds are cheaper than a well cut one, but it will not be as sparkling, as light leaks out from the side of the diamond, which makes the diamond dull and lifeless.




Diamonds are graded by how colourless they are. The lesser the Colour a diamonds has, the more valuable it is. Most diamonds have a little tinge of yellow, while only small percentages are colourless or near colourless.

D to F Colour diamonds are colourless and they are known as Collection colours. They are rare and highly desirable.

While G to I Colour is near colourless, and it is widely used in most Jewellery.

From J Colour onwards to Z, a yellow tinge can be easily detected.

Fun facts:

Before the colour grading was universalized by GIA, starting from D to Z colour, a variety of other colour grading systems were loosely used. From A, B, C to 0, 1, 2, 3, and even the terms, which can often be misinterpreted.

GIA wanted a fresh start with the Colour grading, without wanting to associate with earlier system. That is why they started the grading with the letter D. (Not because letter D stands for Diamond).






As diamonds are formed deep within the earth, most diamonds have what we call Birthmarks; Inclusions (internal) and blemishes (external). Every diamond has its unique birthmarks, like fingerprints and no two diamonds are alike.

There are 5 factors to consider when giving the Clarity grading; the size of inclusion, the quantity, the position, nature and colour of the inclusion.

As diamonds with no or few inclusions are rare, it in turn affects the price.

But as these Clarity characteristic are microscopic in nature; even down to Clarity grading of SI1, most of these birthmarks are not visible to the naked eye. Most of the clarity characteristics are not easy to spot even under a10x magnification.


Carat is the measurement of the weight of diamond. The bigger the diamond, the more valuable it becomes.

As a fraction of a carat can represent a considerable value in price, exact precision is important. In our profession, diamonds are weighed to a thousandth of a carat. So you get what you pay for, and nothing less.

To achieve an excellent cut diamond from a rough (the original state of diamond before it is cut and polished) up to 60% of diamond rough has to be sacrificed. This is why a well cut diamond is more valuable compared to a poorly cut diamond.

Some choose to sacrifice beauty in order not to waste so much of the precious diamond rough and the end result is an average cut diamond that does not sparkle as much.

We will always recommend diamonds with a Very Good or Excellent Cut grading, and nothing less.



Fun Facts:

The modern carat system started with the carob seed. Early traders used the small but uniform seeds as counterweights in the balance scales. The carat is the same weight in every part of the world.

To help you understand better, 1.00ct is equals to 0.2 grams.


Finding all these information too much to comprehend? Leave it to our friend staff and experts to guide you through!

Contact us at 6338 5702 for inquiries

Prefer to select an expert to help you with your quest to have your ideal jewellery? Try contacting them!

+65 9382 0533 (Lik Xon)
+65 8866 7151 (Elise)