Diamond Characteristics that Determine Quality are known as the Four C’s; Cut, Colour, Clarity & Carat Weight
A diamonds cut will determine how well a diamond reflects light.
When a diamond is cut to good proportions, light is reflected from one facet to another and then dispersed through the top of the stone.
A Diamond Cut With Excellent Proportions will ensure maximum light return. At Robert Paul we sell all standard diamond cuts available; Round, Square, Pear, Heart,Radiant, Cushion, Marquise, Emerald, Baguette and more. We also sell Context Diamonds , Spirit Diamonds, and the very best quality in brilliant cut diamonds, Eightstar Diamonds, Tycoon Diamonds, Asteios Diamonds.
Diamond colour is graded alphabetically from the letter D down to Z, D being the whitest. There are also coloured diamonds with a pure colour such as Pink, Blue, Green & Yellow. These are called “Fancy” coloured diamonds. The most popular fancy coloured diamond is the Pink diamond, mined in the Argyle Diamond Mine in Western Australia. At Robert Paul we sell between D & H in colour. These diamonds are varying shades of white. We also sell natural fancy and treated coloured diamonds.
To determine a diamonds clarity, it is viewed under a 10x power magnification. Most diamonds have natural minute inclusions, which do not affect the durability of the diamond. A diamond that is virtually free of interior inclusions and exterior flaws is the highest quality. As the grade of clarity lowers in the diamond, the more natural inclusions it will have. Although, from SI and above the inclusions in the diamond are not visible to the naked eye and can only be seen through a 10x power magnifying loupe. At Robert Paul we sell diamonds from SI and above . These diamonds have either no inclusions or inclusions that are not visible to the naked eye. The diamond diagram show how the clarity of the diamonds are graded. The red marks on the diamond indicate inclusions in the stone.
A diamonds weight is measured in carats.
1 carat = 100 “points“, therefore a diamond that is 50 points, weighs .50 of a carat. (Half a carat)
Size is a major factor in determining the value of a diamond, but two diamonds of equal size can have very different values, depending on their Cut, Colour & Clarity.
Carat Weight Diameter
.25 ct 4.10 mm
.38 ct 4.68 mm
.50 ct 5.15 mm
.63 ct 5.55 mm
.75 ct 5.90 mm
.88 ct 6.20 mm
1 ct 6.50 mm