The weight and cut are the last but not least thing to consider when purchasing a diamond ring. Larger size stones are of course highly sought after and fetch a premium price, but focus on choosing a stone the fits well with the design of the ring and is a good match to the wearers personality. Some people prefer large eye catching stones whereas other people will prefer a smaller, more petite size.
Diamonds, like all other gemstones, are weighed in metric carats; Just as a dollar is divided into 100 cents, a carat is divided into 100 points, therefore a 50 point diamond weighs 0.50 carats and would be called half a carat, a 25 point diamond would be a quarter carat and so on.
Needless to say, the carat weight alone will not be the only consideration in buying a diamond. The other members in the Four Cs - Colour, Clarity and most importantly, Cut grade - are what make the diamond special and have a great impact in establishing the value and cost of any particular diamond.
The cut grade of a diamond is the most important factor in the overall beauty of the stone. The cut is what gives the diamond its sparkle, fire and brilliance, and consists of three main factors:
Proportions – The proportions of the diamond must be as close to 'ideal' as possible. If the diamond is cut too shallow, the light will leak out of the bottom of the stone. If the stone is cut too deep, the light will leak out of the side of the stone.
Symmetry – Facets are compared in opposing pairs and must match their opposing facet perfectly.
Polish – The polish of the stone is the final touch in the cutting process where all the imperfections, abrasions and scratches are carefully polished off to give the diamond a mirror shine.
All of the above factors are crucial in determining the cut grade of the diamond, and must be of the highest quality and craftsmanship to bring out the true beauty and fire in a diamond.
Diamonds are graded Excellent, Very Good, Good, Fair and Poor.
In 1919, Marcel Tolkowsky, a Belgium diamond cutter, published his determinations for the most attractive and balanced cut for round brilliant diamonds. His proportions where based mostly on mathematical calculation involving the critical angle of diamond (the angle at which light bends when it enters a diamond). These dimensions and proportions resulted in a spectacularly beautiful diamond and was given the name ‘The American Ideal Cut’.
In recent years where Cut (proportions) has become a much more important aspect than it had been in the past, cutters have endeavoured to produce the brightest, most scintillating diamond possible, and at the same time, produce this stone by saving as much weight from the rough diamond as they can. They have done this with great results producing a beautiful diamond at a competitive price.
Please note that only round brilliant cut diamonds come with a 'cut grade'. The 'ideal cut grade' has only been formalised by researchers for round brilliant cuts.
For all other shapes, or fancy shapes, the grading report will only state the polish quality and symmetry.