Diamonds: Everything you need to know about diamonds! © Sondra Francis

There is probably no other word in the English language that creates as much excitement for so many women than diamond. Diamond is a wondrous gemstone: its hardness is unrivaled by any other substance. A properly cut diamond has outstanding brilliance and dispersion that is second to none. At one time diamonds were reserved to adorn royalty; but today they are the most popular and available gemstone for everyone. Shopping for diamonds can be simple if a buyer is familiar with the characteristics known as the four C's. Diamonds are easier to shop than other gemstones for because diamonds have an accepted system for grading that is universal.

How to Shop for a Diamond

If you are shopping for a large diamond, .75 carat or more, you should look for a loose stone, or ask the stone be removed from the mounting if possible. When it is loose ask to see the stone weighed. Have the seller show you its color grade and show you its flaws under magnification. Look at the diamond in ordinary light, rather than under spot lights.

Keep in mind that all diamonds do not look alike, to see the differences it is important to look at a few and compare them. It is especially important to look at them under normal lighting conditions, not just under the intense "diamond lights" that are prevalent in jewelry stores.

Carat Weight and Diamond Pricing

Diamond prices are well defined according to carat weight. For stones under l.00 carat, there are ten divisions of sizes that each have their own price structure. As diamonds become larger in size the per carat price goes up steadily up to five carats. Larger diamonds have their own price structure based on their extreme rarity and demand.

For each size classification of colorless or nearly colorless diamonds, there are ten clarity grades and ten color grades used for pricing. This gives one hundred possibilities of price per carat for each particular size, not even including fancy colors, which have a completely different price structure. Every jeweler in the country has gotten a phone call asking how much a one carat diamond is going for at that moment; of course, there are a hundred different possible responses unless color and clarity are defined.

Color

Color is the most important factor in determining the price of a diamond at a given size. Generally when we think of diamonds we think of a colorless gemstone or something that appears to be colorless. Fancy color is applied to those diamonds that are visibly intense yellow or gold, pink, blue, green, red, orange, violet or brown.

Natural pinks, blues, greens, reds, oranges, and violets are exceptionally rare and few become available each year. Fine fancy colored diamonds have received mind-boggling prices in auction sales in recent years. At Christie's auction in April, l987 a .95 carat red diamond sold for $926,000 per carat! Yes, we said "rare and expensive!"

Natural fancy yellows and browns are more readily available. Fancy yellow fetch premium prices; fancy browns are usually available at bargain prices. Sometimes, you can also buy colored diamonds that are irradiated and heated to produce into intense yellows, bright blues, green and browns. The irradiated fancy color diamonds are priced much lower than natural fancy colors. Irradiated blue diamonds resemble the color of blue zircons; they do not resemble the natural blue color of diamonds. If you are shopping for fancy colored diamonds, ask the seller the origin of the color. When you buy a fancy colored diamond get the color and the origin of the color-whether it is natural or irradiated-written on the sales slip.

Most of the diamonds mined, sold and worn fall into the colorless to light yellow category. The Gemological Institute of America devised a an alphabetical system for diamond color grading. Letters from "D" to "Z" signify diamonds from colorless to intense yellow. "D" to "F" are grades that are truly colorless; at "G" there is a slight tinge of yellow and each subsequent letter represents an increasing amount of yellow.

Diamonds that have color grades of "G" through "K" will normally "face up" to appear nearly colorless. But from "L" to "Z" there is an obvious yellowness when the stone is viewed face up. Old terms for describing diamond colors, i.e., river, Wesselton, crystal, and others which were common during the early part of the century, do not specifically define color in any scientific manner. These terms are imprecise and confusing, but fortunately they are rarely used today in the United States.

To properly color grade a diamond, it must be loose. The diamond is placed table down, then it is compared to a set of master color grading diamonds. Master stones have been color graded by the laboratory of the Gemological Institute of America; these stones are then used to compare the color of the diamonds to be graded.

It takes an experienced knowledgeable person, generally a gemologist, to properly color grade a diamond. Lighting conditions must be controlled. If the diamond is fluorescent, this must be considered in assigning the ultimate color grade. But you still can easily see color grade differences when diamonds placed table down and compared to the master stones. Ask your seller to show you this.

Diamond prices are most heavily weighted on the color (except for diamonds that have extremely low clarity grades such as I-3). The colorless grades-D, E, and F-carry premium prices because diamonds with these color grades are extremely rare.

Color grade G, H, and I are considered fine colors, but are priced lower than the D to F grades. Colors J and K will look fine when set into a mounting but they are priced considerably lower. Price guidelines used in the trade give prices down to "M" color. "M" and below mean a diamond is are obviously yellow. At this point, the price levels out and does not change until you reach the fancy yellow colors which carry premium prices. Before a diamond is considered a fancy yellow, the color must be intense enough to be pleasing.

Fluorescence

About 30 to 40 per cent of diamonds fluoresce. They usually fluoresce a blue color under long wave ultraviolet light, but yellow, pink, or green fluorescence also is possible. If fluorescence is slight or moderate it may have little effect on the appearance of the stone. A diamond with moderately blue fluorescence may take on a spectacular appearance when viewed in sunlight. It will appear to take on a slight blue cast and probably look better than an equal set one without fluorescence. However, if fluorescence is too strong it may cause the diamond to have an oily appearance. This is a detrimental feature.

Diamonds that fluoresce a strong yellow may assume a yellow cast but this is unusual for stones that do not have a yellow body color. Excessive fluorescence will lower the diamond's value a bit. Slight and moderate fluorescence will not affect price if the appearance in normal light is not affected.                       
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