When jewelers speak of a diamond's color they are usually referring to the presence or absence of color in white diamonds. Color is a result of the composition of the diamond, and it never changes over time. Because a colorless diamond, like a clear window, allows more light to pass through it than a colored diamond, colorless diamond ensures that only a few, rare diamonds are truly colorless. Thus the whiter a diamond`s color, the greater its value.

(Note that fancy color diamonds do not follow this rule. These diamonds, which are very rare and very expensive, can be any color from blue to green to bright yellow. They are actually more valuable for their color.) To grade 'whitness' or colorlessness, most jewelers refer to GIA's professional color scale that begins with the highest rating of D for colorless, and travels down the alphabet to grade stones with traces of very faint or light yellowish or brownish color. The color scale continues all the way to Z.

Diamonds graded D through F are naturally the most valuable and desirable because of their rarity. Such diamonds are a treat for the eyes of anyone. But you can still obtain very attractive diamonds graded G through I show virtually no color that is visible to the untrained eye. And while a very, very faint hint of yellow will be apparent in diamonds graded J through M, this color can often be minimized by carefully selecting the right jewelry in which to mount your diamond. Keep in mind that, while most people strive to buy the most colorless diamond they can afford, there are many people who actually prefer the warmer glow of lower-color diamonds.

Fluorescence is an effect that is seen in some gem-quality diamonds when they are exposed to long-wave ultraviolet light (such as the lighting frequently seen in dance clubs). Under most lighting conditions, this fluorescence is not detectable to the eye. While most gemologists prefer diamonds without this effect, some people enloy it. It's really just a matter of aesthetics.

Buying a diamond ring is an important event for you and your fiancé, but it can be confusing.
Should you go for a larger diamond or choose a smaller stone of higher quality?
Is color an important consideration?
How does the cut affect the stone?
Before you buy a diamond ring, eternity band, bracelet or necklace , take time to really understand the quality factors known as the 4Cs--color, clarity, cut, carat so you feel comfortable juggling them to get just the right combination for you. Knowing how to juggle the 4Cs can enable you to achieve a high-budget look at a reasonable price.

ClarityF-IF-Flawless or Internally Flawless. This diamond has no internal inclusions. Very rare. VVS1-VVS2- Very Very Slighty included. Very difficult to detect under 10x maginification.

VS1-VS2-Very Slighty included (two grades). Minute inclusions invisible to the naked eye and seen only with difficulty under 10x magnification.

SI1-SI2-SI3 Slightly Included (three grades). Minute inclusions Can be seen under 10x magnification and some cases, in SI3 and SI2, inclusions are visible to the naked eye.

I1-I2-I3-Include (three grades). Inclusions visible under 10x magnification as well as to the human eye.

While the presence of these clarity characteristics do lower the clarity grade, and therefore the value of a diamond they can also be viewed as proof of a diamond's identity. GIA certificates include what is known as a "plot" of a diamond's inclusions. Since no two diamonds are exactly the same, comparing the uniqueness of your diamond's clarity characteristics with the plot provided on the diamond certificate offers assurance that the diamond you pay for the same diamond you receive.

While Flawless diamonds are the rarest, and arguably most beautiful diamonds, a diamond does not have to be completely clean to be extremely attractive. Those diamonds with VVS and VS grades can be excellent choices as well. More affordable are those diamonds which gemologists call "eye-clean" - diamonds with no inclusions visible to the naked eye. These diamonds are graded SI

When we speak of a diamond's clarity, we referring to the presence of identifying characteristics on and within the stone. While most of these characteristics are inherent qualities of the rough diamond and have been present since the earlitiest stages of the crystal's growth below ground, a few are actually a result of the harsh stress that a diamond undergoes during the cutting process itself.

If you think about the incredible amount of pressure it takes to create a diamond, it's no surprise that many diamonds have inclusion-scratches, blemishes, air bubbles or non-diamond mineral material-on their surface or inside. Diamonds with no or few inclusions and blemishes are more highly valued than those with less clarity, not just because they are more pleasing to the eye, but also because they are rarer.

Diamonds are graded for clarity under 10x loupe magnification. Grades range from Internally Flawless, diamonds which are completely free of blemishes and inclusions even under 10x magnification, to Imperfect 3, diamonds which possess large, heavy blemishes and inclusion that are visible to the naked eye.

A carat is a unit of measurement it's the unit used to weigh a diamond. One carat is equal to 200 milligrams, or 0.2 grams. The word carat is taken from the carob seeds that people once used in ancient times to balance scales. So uniform in shape and weight are these little seeds that even today's sophisticated instruments cannot detect more than three one-thousandths of a difference between them.

Don`t confuse it with "karat', the method of determining the purity of gold. The process that forms a diamond happens only in very rare circumstances, and typically the natural materials required are found only in small amount. That means that larger diamonds are uncovered less often than smaller ones. Thus, large diamonds are rare and have a greater value per carat. For that reason, the price of a diamond rises exponentiaonaly to its size.

Note that an increase in carat weight does not necessarily translate to a proportionate increase in the way it looks to the naked eye. A2-carat diamond does not appear to be twice as a big as 1-carat diamond, especially if you look at it from the top

Now we want to talk about Cut - probably the most complex of the Four Cs to explain.

You may think of cut as the shape and style of a polished diamond. But when we talk about Cut as a value factor, we're also talking about the proportions, symmetry and finish of a diamond, often called "make" in the diamond trade. A diamond with a "good make" will speak to you.
It's bright, fiery, symmetrical, and sparkles with light. "What makes Cut so difficult to evaluate is that there's more than one way of cutting a diamond to make the most of its optical properties. A well-cut diamond, with well-balanced proportions and high polish, can make light behave in breathtaking ways. The result is a magnificent display of brilliance, dispersion, and scintillation."

The three major parts of a polished diamond, top to bottom, are the crown, the girdle, and the pavilion. Some polished diamonds have a very tiny flat facet at the bottom of the pavilion, called the culet. The large flat facet on the top of a polished diamond is called the table The distance from the bottom of the girdle to the culet is the pavilion depth. A pavilion depth that’s too shallow or too deep will allow light to escape from the side of the stone, or leak out of the bottom. A well-cut diamond will direct more light through the crown.Pavilion depth is only one way of controlling the way light travels through a diamond. Cutting a diamond to produce the maximum return of light depends on the interrelationship between three critical proportions – table size, crown angle and pavilion depth. These can be combined in many ways to yield equally bright round brilliant cut diamonds.

Unfortunately, the term they made up for these other stones was "semi-precious."

Too bad the French terminology was not followed in this instance, or these other stones would have been known as "fine gemstones," which is a much better and more accurate term.

The problem with "semi-precious," and the reason the jewelry indstry essentially banned its use, is that it's a misnomer.

Rubies, emeralds, and sapphires can sell for less $10 per carat, while a fine Paraiba tourmaline, for example, can sell for $20,000 per carat!. For every gemstone, pricing follows common sense: the better the final visual effect of all the quality factors of the stone, the more valuable that stone is. But different varieties of gemstones have different price ranges. This is where the perception factor comes in.

Some varieries are lower in price because they are readily available; some, because the color isn't very popular(brown and yellow stones, for example); some, because the material is relatively soft; and some, because they have all the right stuff but no one knows it.

There are plentry of example of beatifull, rare gemstones costing less than gems that are not so rare -- merely because they prossess a funny name, or people confuse them with an inxpensive variety, or they are of a gem variety few of us are acquainted with.

In the past, the gemstone business was dominated by the big three: ruby,emerald and sapphire. These often are called precious stones, a term probably derived from the French label, "pierres precieuse."