Diamond colour grading, how does it work?

Before you go out and buy your next diamond jewellery item, you might find the following information of interest. The colour of a diamond will effect the price of the jewellery item you have in mind to purchase. If you have any questions please leave a comment and we will do our best to give you a clear answer.

White diamond colour grading is scored on a scale of D through to Z. Diamonds with a colour grading of D are deemed more valuable than a diamond with a score of Z.

A diamond of D grade has no tints of yellow colour in it. This means It’s seen as the purest colour a diamond can be.

As for a diamond with the colour grade of Z you will noticeably see the difference as the diamond will be heavily tinted yellow.

Many professional jewellers will not sell a white diamond below the colour grade of J. Once you see a white diamond at a grade of H through to Z, you can start to see a noticeable difference in the final diamond colour.

So if you have a prized diamond ring in mind, be careful to check for its colour grade. Expect to pay less for a diamond that is graded below the grading of D.

Diamond Colour Chart

We have provided you with a handy diamond colour chart to show how each diamond is scored. You will see a slight colour change in each diamond. However even when we applied a slight change to our diamond images, the changes are almost not noticeable. The same is for real diamonds. It’s hard to detect a minor colour fluctuation with the naked eye.

Colour is one aspect to think about but please also take into consideration:

Diamond clarity
Diamond cuts

D		Exceptional White +	The Exceptional White (+) diamond with a grade of D is the very rarest of the diamond colour range. The diamond will be completely colourless. This makes it the most valuable coloured diamond.	Grade: Colourless.
E		Exceptional White	The Exceptional White diamond with a grade of E is also very rare. The difference between D and E is hard to detect when compared. This diamond is graded colourless. This also makes it very valuable.	Grade: Colourless.
F		Rare White +	The Rare White (+) diamond is the third highest coloured graded diamond achievable. Its graded F as the diamond is colourless when viewed through the crown.	Grade: Colourless when viewed through the crown.
G		Rare White	The Rare White is a fine alternative to the top three colour grades. This colour still makes for an outstanding diamond. Its grade of G is colourless when viewed through the crown.	Grade: Colourless when viewed through the crown.
H		White	The White coloured diamond has a small noticeable colour difference when compared to the top 4 colour grades. It’s grade of H is colourless when viewed through the crown.	Grade: Colourless when viewed through the crown.
I		Slightly Tinted	The Slightly Tinted White is a great staring point if your buying a diamond on a budget. The colour difference is still very slight making it hard to tell the difference when compared to other grades. It’s grade of I is slightly coloured.	Grade: Slightly coloured.
J		Slightly Tinted White	The Slightly Tinted White diamond should really be the last consideration when picking your diamond colour. Anything below this grade will look slightly yellow. Its grade of J is Slightly coloured.	Grade: Slightly coloured.

Who grades the diamonds?

The GIA grades most white diamonds, and they provide a certificate to show the grade awarded to the diamond you might be thinking about buying. The diamonds are accurately measured using equipment contained in a special environment. This allows for the detection of slight changes in each diamond. The diamond industry uses the GIA diamond colour scale for most of the diamonds bought today.

Below is the Wiki diamond colour chart. Note: they have used a sequence of colours that over exaggerated the colour yellow for each diamond. This should give you a better idea of how the scale works, but the actual colour scheme used is not a true representation of how the diamond will actually look.

Diamond colour grading scales

GIA	Status: current	AGS	Status: current	AGS	Status: historical: pre 1995	CIBJO	Status: current	IDC	Status: current	Scan. D.N.	Status: current	Old World Terms	Status: historical
grade and description		grade and electronic colorimeter scale/td>		grade and electronic colorimeter scale		grade		grade and description		grade for .50ct and over	grade for under .50ct	series 1 scale	series 2 scale
D	Colorless	0	0–0.49	0	0–0.75	Exceptional white +		Exceptional white +	Colourless	River	White	Finest White	Jager
E		0.5	0.5–0.99			Exceptional white		Exceptional white					River
				1	0.76–1.35
F		1.0	1.0–1.49			Rare white +		Rare white +	Colourless when viewed through the crown	Top Wesselton		Fine White
				2	1.36–2.00
G	Near Colourless	1.5	1.5–1.99			Rare white		Rare white					Top Wesselton
H		2.0	2.0–2.49	3	2.01–2.50	White		White		Wesselton		White	Wesselton
I		2.5	2.5–2.99	4	2.51–3.0	Slightly tinted white		Slightly tinted white	Slightly coloured	Top Crystal	Slightly tinted white	Commercial White	Top Crystal
J		3.0	3.0–3.49	5	3.01–3.75					Crystal		Top silver cape	Crystal
K	Faint Yellow	3.5	3.5–3.99			Tinted white		Tinted white		Top cape	Tinted white		Top cape
				6	3.76–4.5							Silver cape
L		4.0	4.0–4.49
M		4.5	4.5–4.99	7	4.51–5.50	Tinted colour 1		Tinted color	Slightly coloured to coloured	Cape	Tinted colour	Light cape	Cape
N	Very Light Yellow	5.0	5.0–5.49			Tinted colour 2							Low Cape
O		5.5	5.5–5.99	8	5.51–7.0					Light yellow		Cape	Very light yellow
P		6.0	6.0–6.49										Light yellow
Q		6.5	6.5–6.99
R		7.0	7.0–7.49	9	7.01–8.5
												Dark cape
S	Light Yellow	7.5	7.5–7.99			Tinted colour 3				Yellow
T		8.0	8.0–8.49
U		8.5	8.5–8.99	10	8.51–10
V		9.0	9.0–9.49
W		9.5	9.5–9.99
X		10	10+	10+
Y
Z

For even more information check out the wiki chart.