The color of a diamond has the second biggest impact on its price, after carat weight. Did you know that diamonds come in every color of the rainbow?
When discussing the topic of color in diamonds, you need to differentiate between mostly "colorless" diamonds and "fancy color" diamonds.
Grading "colorless" diamonds involves deciding how closely a stone's bodycolor approaches colorlessness. Most diamonds have at least a trace of yellow or brown bodycolor. The reason colorlessness is most highly valued is that diamonds in these ranges act like prisms, separating white light passing through it into a wide spectrum of colors. The more transparent the diamond, the wider the spectrum of colors. Chemical "impurities" in the diamond will filter out some of the colors which in turn reduces the "fire" effect when light bounces back out of the diamond and into your eyes. Other than "fancy colors". colorless diamonds tend to be more valuable. Rare colors such as blue, pink, purple, or red tend to be very expensive...and very beautiful.
If a diamond does not have enough color to be called fancy, then it is graded in a scale of colors ranging from Colorless to Light Yellow, "D" through "Z". A diamond with a "D" color is considered to be colorless. If the color is more intense than "Z", it is considered fancy. A fancy yellow diamond fetches a higher price than a light yellow diamond.
The Laboratories only grade diamonds which are unmounted, or "loose", and they do so under special light. Once a loose diamond is mounted on a ring, even the trained professional cannot always tell the difference between, say a "D" color and an "E" or "F" color diamond!
While it would be nice if technology brought about the ability to take the guesswork out of grading diamonds, we are not there yet. In terms of color, Sarin, one of the technology leaders in gemological equipment, has come out with a device called the "colorimeter". The concept of the colorimeter is to be able to reliably judge a color impartially. Over the years, the device has improved considerably, however it is not as reliable as the eye yet and sometimes comes out with unexpected results. The one good thing is that the results tend to be repeatable. The labs use them from time to time, but do not rely on them at all. Maybe one day color grading will be done by a machine, the same way measurements are.
How much does "color" affect cost?
Let's take a typical diamond through different color grades and see how it can affect cost. Let's start with a 1.00 carat diamond of K color and VS1 clarity. If you move up to an H color, you will pay approximately an extra $1,700 per carat. Move up to F color, the increase will be approximately $1,100 per carat. Improve the color to D and the increase will be approximately $900 per carat.
Anecdotes from the Lab:
Training someone to become a diamond grader is not always easy. There is actually talent involved and not everyone is cut out for this type of work. It is particularly hard to train people to become sensitive to color.
Some people can confuse hue and saturation. If a diamond has a hue of brown, it can fool some graders into giving the diamond a worse grade than it "deserves". Some embarrassing grades are out there on some brown stones.
It is a known fact that women in general detect shades of color better than men do. It's like the movie "The Devil Wears Prada", when Anne Hathaway can't tell the difference between two blue belts and Meryl Streep lectures her about the names of each shade of blue on each fabric.
To see how talented you are with color, try to look at a chart of the pantone colors. Are they all very different to you?
A final word. Once in a while a diamond comes in with color zones. More than one color or more than one saturation level in a diamond. Those diamonds are fascinating to look at, although not so easy to grade.
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DIAMONDS TUTORIAL NAVIGATOR
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Lesson 1, The 5Cs:
Carat, Color, Clarity, Cut, Cost
Lesson 2, Shapes:
Round, Asscher, Cushion, Emerald, Heart,
Marquise, Oval, Pear, Princess, Radiant
Lesson 3, Articles:
How to Buy a Diamond, How to Sell Your Jewelry,
How to Read a Diamond Certificate,
The difference between a Certificate & an Appraisal,
What is the SI3?,
World's Largest Polished Diamonds,
World's Largest Rough Diamonds, Diamond Facts
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