Coloured Diamond

There are certain diamonds that do not fall in the color category set by GIA and they are known as fancy diamonds.

What do you mean by fancy colour?

Diamonds colour range almost includes every colour of spectrum. But most of the diamonds gives yellow or brown shade. Basically, diamonds colour described as absence of any colour, which indicates the quality of diamonds and also the 4Cs of diamond clarity, diamond carat weight and diamond cut. In this part we will concentrate more on fancy colours diamonds. If brown and yellow diamonds exhibits more colour which is beyond Z grade within the D-Z colour scale are known as fancy colours. So we can say that Diamonds which are outside the range of D-Z scale are known as fancy colours.
The most common fancy diamond used in the industry is ‘Brown’ color. This was one of the first of its kind to be used in the jewellery making. The second most popular fancy colour diamond is a ‘Yellow’, which are also known as “canary”.
The precious and rarest colors are saturated Blue, Pink, Green and Red. Any variants or slight differences in colors have a significant impact on its price. The extremely rare ones are Red, Green, and Blue diamond with moderate saturation and medium to dark tones.
There was no such demands of black diamond until late 1990s, after which the designers used them in jewellery in contrast with small colorless diamonds in pave settings.
Fancy white diamonds having milky white color are also available.
Some diamonds are gray in color and as they contain a high level of hydrogen as an impurity.
While buying fancy color diamonds, the most important factor is Color more than cut and Clarity and also their grading requires specially trained and qualified graders who accurately grade them in specialised laboratories.

Fancy Colours Grading-

In colour grading scale fancy colours starts after Z grade. In case of diamonds which are light in colour or have no colour are evaluated by lab graders from face-down position, in case of fancy colour diamonds face-up or top view of the diamond is evaluated.

Hue, tone and saturation are tested by graders:-

  • Hue: - Exact colour description of diamond.
  • Tone: - it refers to lightness or darkness of diamond colour.
  • Saturation: - It means the strength and power of the colou

Secondary or modifying colours

Secondary or modifying colours are also evaluated, as they influence the overall hue of the fancy colour. For example, a yellow diamond may have a bit of green colour, and will eventually be graded as "Fancy Greenish Yellow." A blue diamond may have a bit of grey secondary colour, and will be graded as "Fancy Greyish Blue” and many more like that.

Terms used for fancy colours in grading reports

Following terms are used for fancy colours:-

Faint, Light, Very Light, Fancy Light, Fancy, Fancy Dark, Fancy Deep, Fancy Intense, Fancy Vivid

color-diamonds

Pricing of fancy colour diamond:-

Hue, tone, Saturation also scarcity and demand of fancy colour diamonds are some of the key factor which are considered, while determining their prices. Diamonds which are purely red in colours are the most highly charged diamonds per carat in the world. Many diamonds i.e. fine yellow, pink, blue and green also charge high prices based upon their quality and size. In natural fancy colours brown diamonds are less costly. In coloured stones, colour plays a supreme role in determining the price of fancy colour stones. But in pricing of colourless diamonds the high clarity and good looking cuts of stones plays an important role.
It is suggested, all the time to the customers, buy diamond jewellery from reliable sellers, if you have some queries regarding your jewellery then you can take a help of competent appraiser.

What are the causes of colour in diamonds?

Trace elements, structural deformations and radiation are some of the reasons which gives fancy colours to diamonds. Some of the common causes of natural fancy colours:-
Yellow diamonds: - produces yellow colour because of the existence of nitrogen
Brown, pink and red diamonds; - It is because of the mixture of some impurities and some structural deformation in crystal lattice.
Blue diamond: - it gets blue colour from boron and probably from hydrogen.
Green diamonds: - it gets green colour from naturally occurring radiation.
Grey and violet Diamonds: - Due to high amount of hydrogen the diamonds reflect grey colour.
Black diamond: -large amount of impurities, which are scattered evenly all over in the diamond.
Orange diamonds: - Structural deformations comprised of trace element like nitrogen.

How does cut affect fancy colour diamond?

Cuts are commonly used in fancy colour diamonds to enhance the colour. There are some specific shapes which help in strengthening fancy colours. If pavilion is too deep, the colour will appear darker to eyes. We can frequently see yellow diamonds that are being designed into radiant shapes since the blend of these mix shapes gives more intensity to the yellow tone. In almost every diamonds, the finishing of the cut based on the irregular surface and how much a cutter can attain in terms of colour quality.

How does diamond fluorescence affect fancy colour?

Diamond fluorescence give more glow to fancy colour. In normal lighting provision fluorescence have no affect on fancy coloured diamonds, but under UV lights or sun light yellow diamonds with yellow fluorescence will be more bright and glowing. Most of the yellow diamonds gives blue fluorescence. Diamonds with complementary fluorescence helps in enhancing the appearance of the colour.