Diamond Color and Grade Buying Guide


Gem Body Color.

Color is one of the most important factors to consider when selecting a diamond because one of the first things most people notice is whether or not the diamond is white, or, more accurately, colorless. It is also one of the most significant factors affecting value.

Color refer to the natural body color of a diamond. The finest and most expensive, “white” diamonds are absolutely colorless. Most diamonds show some trace of yellowish or brownish tint, but diamonds also occur in every color of rainbow. Natural colored diamonds are called “fancy” diamonds.

How to look at a diamond to evaluate color?

In white diamonds, color differences from one grade to the next can be very subtle, and a difference of several grades is difficult to see when a diamond is mounted. Keep in mind that it is impossible to accurately grade color in a mounted diamond. When looking at an un-mounted stone, however, even an amateur can learn to see color differences if the stone is viewed properly.

Because of diamond’s high brilliance and dispersion, the color grade can not be accurately determined by looking at the stone from the top, or face-up, position. It is best to observe color by examining the stone through the pavilion with the table down. Use a flat white surface such as a white business card, or a grading trough, which can be be purchased from a jewelry supplier or the Gemological Institute of America, GIA. Next, view the stone with the pavilion side down and the culet pointing toward you.

What is diamond body color?

When we discuss diamond body color we are referring too much yellow or brown tint can be seen in a white (colorless) diamond. We are not referring to rare natural colored diamonds, which are called “fancy” or “master Fancy” in the trade.

Today, most colorless diamonds in the United States and in an increasing number of other countries are graded in alphabetical scale beginning with the letter D, which designates the finest, rarest, most absolutely colorless diamond, and continuing down through the entire alphabet to the letter Z. Each letter after D indicates increasing amounts of yellowish (or brownish) tint to the body color. It’s easy to understand the color grade, if you just remember: the closer the letter is to D the Whiter the diamond; the closer the letter to is to Z, the more yellow (or more brown) the diamond.

This grading system, with its letter designations, is part of a diamond grading system introduced by the Gemological Institute of America, often referred to as GIA, and is used extensively in the diamond trade around the world. Grades E – F are exceptionally fine and diamonds in this range can be referred to as “colorless,” although technically, E and F are not colorless since they possess a very slight trace of yellow; the tint is so slight, however, that the trade agrees they may be referred to as colorless.

What color grade is most desirable?

The diamonds colors, D, E, and F can all be grouped as exceptionally fine and may be referred to as “colorless,” “exceptional white.” or “rare white” as they are often described by diamond dealers. G and H may be referred to as “fine white” or “rare white.” These grades are all considered very good. I and J colors are slightly tinted white. K and L show a tint of yellow or brown, but settings can often mask the slight tint. Grades M – Z will show progressively more and more tint of color, and will have a definite yellowish or brownish cast; diamonds with a strong yellowish tint are often referred to as cape stones in trade.
Diamond grades D – J seem to have better resale potential than grades K – Z. This does not mean that diamonds having a more tinted color (grades below J) are not beautiful or desirable. They can make lovely jewelry and, depending upon other quality factors and “overall personality,” color. Remember: color is important, but it’s only one of four factors you must learn to weigh as you judge the whole stone.

To what extent does the color grade affect value?

To an untrained eye, discerning the difference in color from D down to H in a mounted stone, without direct comparison, is almost impossible. Nevertheless, the difference in color greatly affects the value of the diamond. A one carat, flawless, excellently proportioned D color diamond might sell for a much higher price than the same stone with H color. The same stone with K color might sell for much less price. And if the stone were not flawless, or well cut, it could sell for much less.

In diamonds over one carat, the more white the stone, the more critical it becomes to know the exact color grade of its effect on value. On the other hand, as long as you know for sure what color the stone is, and are paying the right price, choosing one that is a grade or two lower than another will reduce the cost per carat, and there will be little, if any, visible difference when the stone is mounted. Therefore, for the difference in cost, you might be able to get a larger diamond, or one with a better clarity grade, depending upon what is most important to you.

What is Fluorescence?

If the diamond you are considering is accompanied by a diamond grading report, it will indicate whether or not the diamond has some degree of fluorescence. This is a property that some stones posses which causes 婚戒 them to appear to be different colors in different lights. A diamond that fluoresces might light whiter than it really is in certain light. This is one reason why the color of any fine diamond should always be verified by a qualified gemologist.

If a diamond fluoresces, it normally will produce a bluish, yellowish, or whitish glow when viewed in sunlight or daylight type fluorescent light ( those long tubes you see in the ceiling of many stores and office buildings). To ensure that the true body color is being graded, a professional will always test for fluorescence with a special ultraviolet lamp prior to color grading. Blue Fluorescence is more common than yellow or white. Some white diamonds that produce a blue fluorescence may actually look “blue-white” in the right light. Normally, however, you will not really notice fluorescence with the naked eye
It is also important to know whether or not a diamond fluoresces to prevent any unpleasant surprises. For example, if you buy a “fluorescent” diamond because it seems so “white” when you purchase it (resulting from exposure to fluorescent light in the jewelry store, which, except in the case of fluorescent stones, is the proper light for viewing diamond color), you might be disappointed by its yellower appearance in the evening light where the stone won’t fluoresce.
A white diamond can also fluoresce yellow, and look yellower than it really is. But remember, whatever color is produced by fluorescence, it occurs only in the daylight or fluorescent light.


Leave a Reply

Your email address will not be published. Required fields are marked *