Diamond Education and the 4C’s

Before making such an important and on occasion expensive Diamond purchase, it is important to understand exactly what it is that you are buying.

Let our professional in-house diamond graders educate you on diamonds so you have a better understanding of a diamonds characteristics, making sure that you are backed with knowledge and in the position to make the right choice.

For an instore diamond education session please Contact Us.

Diamond Carat Weight

Carat is a term used to refer only to the weight of a diamond. It is like a gram or kilogram as it measures only weight.

Carat is often confused with the physical size or look of the diamond but it has nothing to do with this. (The confusion may come from gold, where the word carat refers to the purity of the metal)

The weight of Carat comes from “carob” which is the seed of the carob tree. One carat originally meant the weight of one “carob seed”.

Today a carat is equal to 0.2 grams. Just to confuse things, a carat is divided into 100 points, so that a carat weighing 50 points is described as “half a carat”.

Carat is one of the 4C’s of diamonds, the other 3 being Colour, Clarity and Cut of the diamond. If you’d like further explanation of any of these terms, our in-house diamond graders will be happy to clarify them for you. Just contact us!

Diamond Colour

Diamonds are naturally found in a wide selection of colours including pink, champagne, blue, green and intense yellow.

The most common colour range is from a faint yellow or brownish tint to the extremely valuable colourless diamonds. A colourless diamond is graded ‘D’ and is fairly rare.

MDTdesign carry ‘D’ through to ‘G’ colour diamonds which are considered ‘very fine white’.

GIA (Gemological Institute of America) Colour Grading scale


Fancy coloured diamonds, such as yellow diamonds, pink diamonds, or champagne diamonds, are graded on a different colour scale. The more intense the colour of the diamond, the more rare, valuable and usually more desirable a stone is.

If you would like something really unusual, MDT Design also have one of the largest ranges of coloured stones including pink diamonds, yellow diamonds and champagne diamonds Australia has to offer.

Want to know more about how Diamond Colour as well as Diamond ClarityDiamond Cut, and Diamond Carat Weight, all determine the value and beauty of a diamond?

Contact Us to find out more.

Diamond Cut

The Cut of a diamond should not be confused with the shape of a diamond, this refers to how well a diamond is cut, not the shape.

How a diamond is cut influences how brightly it sparkles and so the cut of a diamond is graded using an internationally accepted grading system.

Terms like round, oval, pear and heart are easy to understand as shapes of a diamond but they also describe a type of diamond cut. Terms like Princess Cut, Marquise Cut, Cushion Cut and Asscher Cut are less easy to picture as a shape in your mind. How well each of these shapes of stones are cut will heavily influence brightness and luster with the best diamond cutters in the world choosing to sacrifice the carat weight of the diamond, to achieve a brighter stone that in turn would then cost more.


All these fancy cut diamonds (which means anything but a round cut) do not have a cut grade as every stone can have completely different proportions in terms of length, width and depth. Each of these fancy cut stones needs to be inspected and compared with others in order to find the brightest stone that reflects the most light. Most fancy cut diamonds do have polish and symmetry grades, though this gives no indication of the cut or the brightness of the diamond. Even fancy cut diamonds that have excellent polish and symmetry grades are not guaranteed to be bright stones.

Essentially the skill of a diamond cutter lies in releasing the maximum amount of sparkle and lustre from a piece of uncut rough diamond. While all of the 4C’s of diamonds are important, it is the ‘cut’ that most influences the brightness and sparkle of a diamond. A well-proportioned, well-cut diamond will reflect light from each facet and return that light back through the top of the diamond which is known as the “table”. If the cut of a stone is too deep or too shallow light will be lost through the side, resulting in a dull diamond.

You will be pleased to know that MDTdesign mostly uses ‘Excellent’ cut graded diamonds.

Want to know more about the importance of Diamond Cut and how it, along with Diamond Colour, Diamond Clarity, Diamond Carat Weight and Diamond Shape, determine the value and beauty of a diamond?

Just Contact Us and we’ll be happy to explain it all to you.

Diamond Clarity

Almost all diamonds contain small traces of carbon that did not turn into crystal when the diamond was originally being formed deep in the ground. These are called “inclusions” and ideally a perfect diamond would be completely free of them.

The Clarity of a Diamond is a system of grading diamonds by how many of these inclusions it has. Preferably the inclusions should not affect the brilliance or brightness of the diamond, nor affect the reflection of light within the diamond that would lower its lustre. The more a diamond is free of inclusions, the higher its Clarity grading.

The grading system uses terms like SI, VS and VVS, which simply mean Slight Inclusions, Very Slight Inclusions and Very Very Slight Inclusions, and then numbers like 1, 2 and 3 to indicate finer differences in grades. For example any diamond with inclusions that are not visible to the naked eye and do not affect the look of the stone to the naked eye should be graded SI2 or higher.

Clarity Grading Scale


However we have noticed a slight shift in grading over the years with many stones up to VS2 grading having inclusions that are visible to the naked eye.

For this reason MDTdesign carefully and independently inspects every diamond before purchasing and if we find that the diamond does have inclusions visible to the naked eye, we will not sell or stock that diamond.

This is why it is extremely important to carefully visually inspect any diamond you are considering purchasing. There is a big difference between a good SI2 graded diamond and a bad SI2 graded diamond as there is with all the other gradings. This difference is reflected in the diamond’s price.

At MDTdesign, we only sell diamonds rated at the top end of the Clarity scale, mainly ‘VS’ (Very Slight Inclusions) and ‘SI’ (Slight Inclusions) clarity diamonds but, as with colour, if you would prefer a higher clarity graded diamond we are happy to get you what you want. We will be glad to show you in store the differences between the Clarity of various diamonds and help you understand what is true to its definition.

We would much rather you have a high end graded SI2 diamond rather than a bad quality SI1 clarity diamond that is not true to its Certificate.

Some advice about buying diamonds.

Please note that Diamond Certificates can be wrong or just lenient and you should not buy a stone purely based on its certification without inspecting it yourself or having it independently inspected.

Also we have discovered recently that many diamonds called ‘clarity enhanced diamonds’ are being sold around Australia. These stones are of poor quality and have either been laser drilled to remove large black inclusions or have had fractures in the stone ‘filled’.

At MDTdesign, we DO NOT SELL this quality of diamonds nor would we recommend buying one.

We will be happy to further explain the importance of Diamond Clarity, Diamond Colour, Diamond Cut and Diamond Carat Weight, all characteristics that determine the value and beauty of a diamond.


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