The Diamonds 4C's
Every naturally formed diamond is unique and interesting in its own way with distinguishing features and characteristics that make them stand out. The 4C’s, labelled as carat weight, clarity, colour and cut—are the internationally accepted standards for assessing the quality of a diamond set by the Global Institute of Diamonds GIA.
Diamond Carat

Contrary to belief, a diamond’s Carat weight is measured by it’s actual weight and not its size. Many assume that the bigger the diamond the more value it has but there are many other factors that determine how much it will cost to buy. Different shaped diamonds have varying carat weights. The diagram above illustrates the varying sizes of a round diamond from 0.1ct to 2.0ct. Here at Luminary Fine Jewellery, we take pride in the quality of our diamonds and ensure that each stone is cut to ensure maximum beauty and lustre over physical size.
Diamond Clarity

Diamond clarity is a quality of a diamond related to the existence and visual appearance of its internal characteristics which are called inclusions, and surface defects called blemishes. If you are looking to invest in a diamond ring or a pair of earrings then it’s important to know why the price points change depending on the different types of diamond clarity.
Diamond Colour

When diamonds are formed naturally, they absorb natural gases such as Nitrogen which when reflected in the diamond can take on a yellow hue to the naked eye. Diamonds are graded in relationship to their natural colour from D through to Z, with D being a white colourless diamond and Z being a slightly yellow stone. This grade has been set and approved by the Gemological Institute of America GIA. To maintain visual quality and beauty in diamond jewellery, Luminary Fine Jewellery generally work within the grades D-J with even the lower end of the scale being difficult to see any colour without magnification.
Diamond Cut

Diamond cut refers to the specific proportions of a diamond. These proportions include the facets and cuts that are made to a rough diamond to turn it into its desired shape such as Round Brilliant cut or Princess Cut for instance. What is important though is how these cuts and facets allow the reflection and refraction of light, essentially light bouncing off or light passing through the stone, and how this interacts with your eye. To create the “fire”, often associated with a diamonds sparkle, is the difference between how much light passes through the diamond and how much light bounces off the surface into you eye. If the cut proportions are ideal more light will reflect back through the stone as shown in the Very Good and Excellent cuts above. If the proportions are not so good more light will pass through the stone and five a poor or fair light array to the naked eye.
Of course, the 4C's are just a starting point in understanding the many facets of a diamond.
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