Diamond’s color plays a key role in determining diamond’s value and beauty and this is the reason why sometimes jewelers set diamonds in groups of similar colors. The diamond color scale usually starts from D meaning best blue White to Z meaning dark colored diamonds. This scale has been widely accepted in almost all countries superseding some older scaling systems.It’s also important to mention that professional grading labs judge color of individual diamond from the side of the diamond and not from the top. Diamonds graded D-F are considered "colorless", G-J are considered "near-colorless", K-M are "slightly colored", N-Y usually appear light yellow or brown.Chemically speaking perfect diamond is perfectly transparent with no color, but in reality there’s no absolutely perfect diamond. Diamond’s color depends on chemical impurities and structural defects in crystal lattice of diamond.Diamond’s color can detract or enhance its value which depends on the hue and intensity of diamond’s coloration which can have great effect on diamond’s price. For instance if there’s a detectable yellow hue in diamond this will increase the price of the diamond while on the other hand intense blue color will be much more expensive.Majority of diamonds used in jewelry pieces are white diamonds. Nitrogen is the most common impurity giving diamond yellow or even brown color. Rarity is very important factor when talking about diamond’s color because for instance diamonds graded Z are rare and therefore expensive and so are bright yellow and some other colors.Only yellow and brown hues are often, except earlier explained exceptions meaning that diamonds of all other colors are rarer and therefore more expensive. These colored diamonds are often labeled as “fancy” diamonds because of unusual colors of these diamonds. There’s also a rating system for this diamonds developed by gemologists although not in common use because of rarity of these diamonds.CUTCut refers to the manner in which the diamond has been shaped, namely to the proportion, symmetry and finish of a polished diamond. The cut of certain diamond describes the quality and the skilled hand of the master cutter.Cut gets often confused with shape because there are a number of traditional diamond’s shapes. Round brilliant diamond is the most popular shape. Round brilliant diamond if well-cut reflects the maximum light and sparkles more than any other used shape. Round brilliant diamonds are guided with mathematical guidelines for the ratios of angle and length in order to reflect maximum amount of light. Round brilliant diamond is the most expensive shape because 50 % of the rough diamond gets lost while cutting a round shape which is much bigger loss than other shapes.Second most popular technique is known as “princess cut diamonds” which is a square shape. This technique is used rarely compared to round brilliant diamonds, because 80-85 % of diamonds gets cut to round brilliant and only 5-10 % are "princess cut diamonds".Cutting technique is all about getting the better sparkle and is vital factor to visual impression of diamond. Diamond cutting is a technique that has been developed through many centuries with its greatest moments in person of Marcel Tolkowsky. This mathematician and gemologist developed the round brilliant cut when he calculated ideal shape to return and scatter light when watching diamond from above. This is the table of Tolkowsky’s perfect dimensions.Tolkovsky defines ideal dimensions to have:
Table percentage (table diameter divided by overall diameter) = 53%
Depth percentage (Overall depth divided by the overall diameter) = 59.3%
Pavilion Angle (Angle between the girdle and the pavilion) = 40.75°
Crown Angle (Angle between the girdle and the crown) = 34.5°
Pavilion Depth (Depth of pavilion divided by overall diameter) = 43.1%
Crown Depth (Depth of crown divided by crown diameter) = 16,2 %This ideal Tolkowsky’s dimensions have unfortunately very small area in which diamond can be considered perfect and any declination from these dimensions means less reflected light. Since today is a certain financial premium for a diamond that weighs 1,0 carat or more, many diamonds are being cut very poorly just to get pass this magical weight.In order to achieve ideal, round brilliant diamonds aren’t allowed to have depth percentage that is bigger than 62,5 %, and overall diameter of typical round brilliant 1,0 carat diamond should be about 6,5 mm, because diameter of a round brilliant should be about 6,5 times bigger than the cube root of carat weight.Of course, definition of ideal cut is sometimes very subjective and therefore controversial. Although this mathematical model of Tolkowsky was a real breaking point, it’s been superseded by the GIA Facetware software.Some fancy cuts like baguette, marquise, briolette pear cuts are used too although they aren’t holding the same precise Tolkowsky standards and are great deal influenced with fashion.Diamond cutters for instance prefer more princess cut style than the round brilliant because much less material is wasted in princess cut. Some cuts even include extra facets, although their improvement value compared to Tolkowsky's model stays doubtful.Quality of the cut is by many considered to be most important thing when judging beauty of individual diamond because well cut diamond often appears bigger than it really is and has better qualities of color and clarity. That’s why this technique is very important because quality of the cut determines eventual price of individual diamond. Despite the standard called Facetware that was set by GIA, many different theories about ideal cut still exist and are often subject of many controversies.
Table percentage (table diameter divided by overall diameter) = 53%
Depth percentage (Overall depth divided by the overall diameter) = 59.3%
Pavilion Angle (Angle between the girdle and the pavilion) = 40.75°
Crown Angle (Angle between the girdle and the crown) = 34.5°
Pavilion Depth (Depth of pavilion divided by overall diameter) = 43.1%
Crown Depth (Depth of crown divided by crown diameter) = 16,2 %This ideal Tolkowsky’s dimensions have unfortunately very small area in which diamond can be considered perfect and any declination from these dimensions means less reflected light. Since today is a certain financial premium for a diamond that weighs 1,0 carat or more, many diamonds are being cut very poorly just to get pass this magical weight.In order to achieve ideal, round brilliant diamonds aren’t allowed to have depth percentage that is bigger than 62,5 %, and overall diameter of typical round brilliant 1,0 carat diamond should be about 6,5 mm, because diameter of a round brilliant should be about 6,5 times bigger than the cube root of carat weight.Of course, definition of ideal cut is sometimes very subjective and therefore controversial. Although this mathematical model of Tolkowsky was a real breaking point, it’s been superseded by the GIA Facetware software.Some fancy cuts like baguette, marquise, briolette pear cuts are used too although they aren’t holding the same precise Tolkowsky standards and are great deal influenced with fashion.Diamond cutters for instance prefer more princess cut style than the round brilliant because much less material is wasted in princess cut. Some cuts even include extra facets, although their improvement value compared to Tolkowsky's model stays doubtful.Quality of the cut is by many considered to be most important thing when judging beauty of individual diamond because well cut diamond often appears bigger than it really is and has better qualities of color and clarity. That’s why this technique is very important because quality of the cut determines eventual price of individual diamond. Despite the standard called Facetware that was set by GIA, many different theories about ideal cut still exist and are often subject of many controversies.
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