Diamond color is a measure of the presence or absence of color in a diamond, and is graded on a scale from D (colorless) to Z (light yellow or brown).
When it comes to white diamonds, the closer to colorless a diamond is, the more desirable and expensive it is.
Other diamond colors e.g. pink, blue, or green aren’t graded on this scale and have their own grading criteria and grading terminology.
This diamond color guide is part of Modern Jeweler’s “Diamonds 101” series. Its purpose is to help you understand diamond color so you can choose the best color grade for your next diamond purchase.
In this article, you’ll learn:
- The historical background of the diamond color scale and why it confusingly starts at ‘D’
- What causes diamond color
- How diamond color is graded
- How color affects the appearance, price, and value of a diamond
You’ll also learn the difference in diamond color in lab-grown and natural diamonds as well as what to consider when choosing the best diamond color grade for you.
- Diamond color measures how white or yellow a diamond is, with the absence of color being more highly valued.
- The diamond color grade ranges from perfectly colorless (D) to a light yellow/brown tint (Z). There is no A, B or C grades in diamond color.
- Perfectly colorless diamonds are the rarest, which is why they’re more valuable and expensive, while diamonds with a brown or yellow tint are considered lower quality and less desirable.
The Diamond Color Scale
Although diamonds occur naturally in a variety of colors, including pink and blue, we usually tend to think of white diamonds when purchasing engagement rings.
White diamonds are actually very rarely white – the vast majority actually have subtle tints, usually ranging from light yellow to light brown.
Before GIA (Gemological Institute of America) created the diamond color grading scale used today, there was no universal standard to define diamond color and no scale to show how a diamond would compare against others.
Some manufacturers would use a grading system from A to C, while others would use numbers. However, these grading methods weren’t applied consistently across every manufacturer in the diamond industry, which made comparing diamonds very difficult.
In the 1950s, GIA created the scale that is now considered the industry standard and is used across all retailers worldwide.
To avoid confusion with the original A to C grading scale, the GIA scale ranges from D to Z, with each letter grade representing a narrow range of color. Most diamonds used in jewelry sit somewhere in the A – M range:
The difference between adjacent grades is very subtle and can be almost invisible to the untrained eye. The most commonly-used colors are in the ‘colorless’ to ‘near colorless’ range:
- Diamonds that are graded D-F are considered perfectly colorless and are awarded the highest grades on the diamond color chart. colorless diamonds are incredibly rare and, consequently, are priced the highest.
- Diamonds that are graded G-J are considered nearly colorless – these have very little color and it can be difficult to see with the naked eye. It can take a trained gemologist to differentiate between colorless and near-colorless diamonds.
- Diamonds that are graded K-M are faint and have a slight color to them. The larger the diamond, the easier it will be to spot the slight color.
- Diamonds that are graded N-R are very light and have a faint yellow tint that’s visible to the naked eye.
- Diamonds that are graded S-Z are light and have a noticeable yellow or brown tint, which is why they have the lowest rank on the diamond color chart.
Now, let’s explore the main factors that affect diamond color.
How Do Diamonds Get Their Color?
There are two things to consider when we look at diamond color.
The first is the actual color of the diamond as it’s graded on its report. The other is the color that a diamond actually looks, which can be dependent on environmental factors, e.g. the type of metal that the diamond is set into or even the type of light that is shining on the diamond.
The graded color of a diamond is dependent on the amount of impurities in the diamond. These were present when the diamond was formed and the type and amount will determine the diamond’s color.
Diamonds can fall into two different categories, depending on the type of impurities they contain: type I and type II diamonds.
- ‘Type I diamonds’ have nitrogen atoms present in them, which can result in a brown or yellow tint. These are the diamonds that are measured on the GIA color scale.
- ‘Type II diamonds’ don’t have any nitrogen impurities, but there are other elements present that give the diamond its color. colored diamonds fall under the type II category – these are extremely rare but make up a large part of Australian diamond production.
How diamond shape affects color
Certain diamond shapes can also affect the color of a diamond – some shapes, like pear or marquise, are more prone to bring out the yellow tint in a diamond, particularly at sharper ‘points’.
Diamonds with broad facets, step cuts or larger tables, like emerald cuts, are known for accentuating a yellow tint or color present in a diamond.
This H color emerald cut diamond shows the yellow tint much more obviously than the round brilliant H color diamond above.
Other shapes can display color differently in different parts of the diamond, with the areas that are better at reflecting light appearing whiter.
In the H color pear-shaped diamond below, the section on the right has a similar cut to a round brilliant diamond, which means it reflects a large proportion of the light. This section appears whiter than the pointed end of the diamond which is less effective at reflecting light and which displays yellower tones more obviously.
The lighting conditions that a diamond is viewed under can affect the perceived color. For instance, a diamond can look whiter under fluorescent lighting but show more color under diffused lighting typically found at home.
How metal used in a ring’s setting can affect diamond color
Another factor that can affect the appearance of a diamond’s color is the color of the metal used in the setting.
With white metals, like platinum or white gold, it can be a good idea to choose a higher color grade (H or above) to ensure the diamond appears colorless and doesn’t take on a yellowish hue in contrast with the metal.
However, it’s not necessary to choose the highest color grades (D, E, or F), as the difference in appearance may be minimal and not worth the extra cost.
For yellow gold settings, the warm hue of the metal can help to mask the presence of some color in the diamond. In this case, you can opt for a slightly lower color grade (I or J), as the diamond will still appear relatively colorless against the yellow gold. This can be a more budget-friendly option while ensuring that the diamond doesn’t look yellow.
If we compare an I color diamond in a white setting and a yellow gold setting, you can see that the diamond in the white color setting shows the warmer tones of the I color more obviously:
Similarly, for rose gold settings, the warm, pinkish hue of the metal can also help to disguise some color in the diamond. Choosing a diamond with a lower color grade (I or J) should still provide a beautiful appearance without the diamond appearing yellow.
The exact combination of setting color and diamond can come down to personal preference, but choosing an appropriate color for the setting can free up some budget to spend on other attributes of the diamond.
How lighting conditions affect diamond color
The lighting conditions that a diamond is viewed under can affect the perceived color.
For instance, a diamond can look whiter under fluorescent lighting but look darker and show more color under direct sunlight which isn’t entering the diamond directly through the top table of the diamond.
Here’s the same diamond in three different lighting conditions:
While this may not affect the color of diamond you choose, it’s useful to understand that diamond color won’t always appear the same – a diamond may appear lighter or darker, whiter or more yellow, depending on the lighting conditions.
Understanding Diamond Color Grading
Before we examine how the color of a diamond can impact its appearance and value, it’s worth understanding how a color grade is assigned.
Diamond color is graded by comparing a diamond to a set of ‘master stones’ under controlled lighting and viewing conditions:
Gemologists evaluate a diamond’s color by placing the diamonds face-down (upside-down from the usual angle from which we see diamonds) on white paper.
By positioning the diamond this way, less white light is reflected through the diamond, which means that gemologists can judge the color more accurately.
From the top, the colors are quite difficult to see.
When viewed from the side, the diamond reflects less light, which makes the faint yellow much easier to see:
The grading process is repeated several times by different gemologists to ensure that the gemologist’s grading is accurate.
The same diamond can look different when examined from a different viewpoint. Take, for example, this 1-carat G color round diamond, the top view and the side view look quite different.
How Diamond color Affects Price
A diamond’s color can significantly affect its price and value.
Colorless diamonds are considered the purest and rarest – they’re the hardest to find in nature and as a result they’re the most desirable and expensive.
Even within ‘colorless diamonds’, there is a significant difference in pricing within the D-F diamond color grade. If all the other diamond qualities are the same, the price difference between the diamonds in the D-F range can be thousands of dollars.
To demonstrate, we’ll compare two diamonds with the same characteristics – 1-carat, excellent cut, VS2 clarity, but different color grades.
The first diamond is D-colored and priced at $8,080:
If we reduce the color grade to ‘F’, but keep all of the other attributes the same, the price drops to $5,140:
As you can see, the overall pricing difference comes to almost $3,000.
Once mounted in a ring, these two diamonds would be almost indistinguishable from each other.
Lab Grown color vs. Natural Diamond color
Both lab-grown diamonds and natural diamonds are graded using the same diamond color scale, ranging from D (colorless) to Z (light yellow/brown).
While lab-grown and natural diamonds should be chemically identical, there can be a difference in terms of how diamond color presents due to the difference in how natural and lab-grown diamonds are formed.
There are two methods used to make lab-grown diamonds: High-Pressure-High-Temperature (HPHT) and Chemical Vapour Deposition (CVD). The two methods can result in different ‘undertone’ colors being displayed in a diamond.
HPHT diamonds are grown under extreme heat and pressure conditions that mimic the natural conditions under which diamonds form in the earth. After this initial process, a second heating and cooling process is sometimes applied called ‘annealing’, which aims to improve the diamond’s color. Diamonds that are annealed may absorb trace amounts of boron during the process, which can give HPHT diamonds a blueish hue.
CVD diamonds, on the other hand, are grown in a specially prepared gas cloud within a chamber, where other trace elements like nitrogen can be present. These elements can cause a brown or grey hue in CVD lab-grown diamonds.
While it’s always a good idea to look for these undertones in lab-grown diamonds, they may not be present at all or may not be visible to the naked eye.
Diamond Color in the USA: What You Need To Know
When you’re purchasing diamonds in the US, there are some specific considerations to keep in mind.
Among the things you should consider are local certification and grading standards and how these may differ from GIA. In the US, the primary diamond grading lab is GIA, but there are some other local grading labs you may encounter, like the AGS (American Gem Society).
It’s common for different diamond grading labs to have slightly different criteria or methods for grading diamonds than international grading labs, which can affect the consistency with GIA and other more common grading reports.
If a diamond you are considering is accompanied by a grading report from a different US lab than GIA, it’s always a good idea to discuss color grades with your jeweller to ensure that it matches your expectations.
Things to Consider When Choosing the Best Diamond Color Grade for You
We hope our guide on diamond color helped you get acquainted with the basics of the diamond color grade and learn how a diamond color can affect its appearance and value.
Choosing the perfect diamond color grade for your needs and budget will depend on several factors, including the shape you’re going for, the diamond setting, and its size.
What to focus on:
- Balancing color with Other C’s: color is just one of the Four C’s (Cut, Carat, Clarity, color) of diamond quality. It’s important to balance your preference for color with these other factors. A diamond with a perfect color grade but a poor cut can look less brilliant than a diamond with a slightly lower color grade but excellent cut.
- Consider the Setting: The color of the setting can influence the appearance of the diamond’s color. For example, a slightly yellow diamond might appear more colorless in a yellow-gold setting.
- Personal Preference: Remember that the “best” color is largely a matter of personal preference. Some people prefer the icy coolness of a colorless diamond, while others prefer the warm tones of a diamond with slight yellow hues.
What to watch out for:
- Misrepresentation of color: Be wary of misleading language like “blue-white” diamonds. These terms can sometimes be used to make lower grade diamonds seem more appealing.
- Lighting Conditions: The lighting under which you view a diamond can greatly affect its perceived color. Be aware that some jewellers may use lighting that makes diamonds appear whiter.
- Undisclosed Treatments: Some diamonds may be treated to improve their color. Make sure any treatments are disclosed, as they can affect the diamond’s value.
Before purchasing a diamond, it’s important that you get acquainted with the 4Cs to make an informed decision and balance the diamond qualities to get more bang for your buck. Doing your own research on the 4Cs is a great way to learn how these diamond qualities interact with one another and will be key to getting a beautiful diamond at a fair price.