03 9439 3111

Diamond Grading

Diamond is the hardest of all natural substances and along with this, it has a high refractive index which means when light enters the stone it is broken up into all the colours of the spectrum. This brilliant fire is the most outstanding feature of the diamond. All white diamonds are evaluated by considering the four following properties of each diamond.

The Four C’s


The diamond has an extraordinary ability to reflect and refract light, making it the most brilliant of all gemstones. Irrespective of the diamond’s shape, eg. Brilliant, Princess, Baguette, Marquise, Emerald, Pear or Heart, to mention a few, these shapes, if not cut skillfully in the correct proportions, will not reveal the diamond’s full beauty. The quality of the cut is of paramount importance.


With the classic white diamond the colour can vary from a straw colour right up to an absolutely pure white, the latter traditionally being the most sought after form of diamond. In recent years however, coloured diamonds have become more popular with some of the very rare colours being red, green, pink, blue and canary yellow. The Australian diamond mines are famous for producing a wonderful range of coloured stones in particular pink along with colours from a delicate champagne to a rich cognac. These coloured diamonds are now much more in demand.


Diamond is a substance formed naturally millions of years ago and all diamond has varying degrees of purity. Generally this takes the form of small black crystals, white specks and cleavage splits all of which are referred to as inclusions. If a diamond is completely free of any such inclusions it is described as ‘Flawless’ and if it has inclusions that are observable with the naked eye it is described as Pique.

Carat Weight

The carat is a measurement of weight, 0.2 of a gram to be exact. If your diamond weighed 0.2 of a gram it would be a one carat diamond and extremely rare, something like one in a million. Most diamonds weigh less than one carat, so the carat is divided into 100 points to express this. A half carat diamond is 50pts, a quarter carat 25pts and so on.


Always remember the most important aspect of your diamond is how it looks to your eye or how it will appear in your ring. The 4c’s and laboratory certificates should be used as a guide, unless the diamond you are considering looks bright and lively then information written about it does not mean much. Your diamond’s value is always derived as a result of all the above qualities with the cut being of paramount importance. Aaron Wilson specialises in choosing diamonds that not only look good on paper but more importantly look bright to the eye. 


A reputable diamond certificate is prepared by an independent laboratory specifically set up to evaluate diamonds before they are set into a piece of jewellery. 

The most respected certificates internationally are GIA, Gemological Institute of America or HRD, High Diamond Council of Antwerp. 

Diamond Certificates are different to a valuation prepared by a qualified Jewellery Valuer. 

Marks... Our guarantee of quality 

When you purchase an article of diamond jewellery designed and made in our workshop you are assured that the highest standards of materials and craftsmanship are employed in its making. To support this statement each article is stamped with the Designers/ Makers Mark and the Metal Purity Mark. 

Please remember that a piece of jewellery which is worn everyday will wear more quickly than one which is only worn occasionally. Naturally we cannot be responsible for normal wear and tear, but our workshop is able to offer continued service throughout the life of the article. Please take the time to have a free check up of your jewellery at least once a year.