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Carat Weight

The size of a diamond has the biggest impact on its price. The metric carat, which equals 0.20 gram, is the standard unit of weight for diamonds and most other gems. If other factors are equal, the more a stone weighs, the more valuable it will be.

1 ct.
200 milligrams
1/5 gram
100 points

Carat Weight should not be referred to the dimensions of diamond.It refers to weight only. Why the distinction? Because weight can hide in different parts of the stone. You can have a) well-cut, b) deep, or c) shallow Diamonds. Some may appear larger than others due to its cut.

Prices of diamonds are expressed in the trade as a price per carat. So when we say that the Carat Weight has the biggest impact on the price of the stone, we refer to the unit price per carat, not just the overall price of the whole stone.

Example 1:
Diamond "A" = 0.25 carats and costs $1,000 per carat. $1,000 x 0.25 = $250/stone.
Diamond "B" = 0.50 carats and costs $1,250 per carat. $1,250 x 0.50 = $625/stone.

How "big" is a carat?

Many people would like to "understand" carat sizes in real terms. Here's a simple trick to get an idea. Simply take a ruler, and look at the table below. These are some approximate, sample carat-weight to diameter-widths for popular sizes.

0.25 ct. - 4.1 mm	0.50 ct. - 5.2 mm
0.75 ct. - 5.9 mm	1.00 ct. - 6.5 mm

How much does "carat weight" affect cost?

The effect of all the different properties of Diamond on Cost is discussed in more detail in the cost. section. For carat weight, let's take a typical Diamond for an example, and see what happens when we take it through different carat weights.

A Diamond of G color and SI1 Clarity will be in one Category of prices when it is between 0.50 - 0.69 carats. When you take that same quality Diamond and increase the size to the next price category, which is the 0.70 - 0.89 carat range, the price increase will be approximately $1,100 per carat. Increase to the 0.90 - 0.99 carat range, and the price increase will be approximately another $800 per carat. Increase to 1.00 - 1.49 carat range, and the increase will be approximately another $800 per carat. If you increase to the 1.50 - 1.99 carat range, the price increase will be approximately $1,200 per carat.

Color

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?

Grading color in the normal range involves deciding how closely a stone's bodycolor approaches colorlessness. Most diamonds have at least a trace of yellow or brown bodycolor. With the exception of some natural fancycolors, such as blue, pink, purple, or red, the colorless grade is the most valuable.

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 "S". A diamond with a "D" color is considered to be colorless. If the color is more intense than "P", 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!

How much does "color" affect cost?

The effect of all the different properties of Diamond on Cost is discussed in more detail in the Cost section. For color, let's take a typical Diamond for an example, and see what happens when we take it through different color grades.

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.

Clarity

The clarity of a diamond refers to how clear, or "clean" the diamond is. The more "clean" the diamond, the higher the price. Most diamonds have "imperfections" in them. The clarity scale is a measure of the severity of those imperfections or "inclusions" as it is known in the trade.

For example, a deep break in a diamond which is not that visible when you look at the stone face-up, could sometimes have a greater impact on the clarity of a stone, than a small black crystal which you can see very clearly face-up.

The following is a Diamond clarity-scale:


FL IF	VVS1 VVS2	VS1 VS2	SI1 SI2	I1	I2	I3

FL	IF	VVS¹	VVS²	VS¹	VS²	SI¹	SI²	I¹	I²	I³
Flawless- Internally Flawless		Very Very Slightly Imperfect		Very Slightly Imperfect		Slightly Imperfect		Imperfect

FL-Flawless

These stones have no imperfections inside or on the outside of the stone under the magnification of a loupe of 10 power.

IF-Internally Flawless

These stones have no inclusions under a loupe with a 10 power magnification.

VVS¹,VVS²-Very Very Slightly Imperfect

These stones have very small inclusions which are very difficult to see under a loupe with a 10 power magnification.

VS¹,VS²-Very Slightly Imperfect

These stones have small inclusions which are slightly difficult to difficult to see under a loupe with a 10 power magnification.

SI¹,SI²-Slightly Imperfect

These stones have inclusions which are fairly easy to see under a loupe with a 10 power magnification, or visible to the naked eye.

I¹,I²,I³-Imperfect

These stones have inclusions which range from eye visible to very easily seen to the naked eye.

How much does "clarity" affect cost?

The effect of all the different properties of Diamond on Cost is discussed in more detail in the Cost section. For clarity, let's take a typical Diamond for an example, and see what happens when we take it through different clarity grades.

Let's start with a 1.00 carat Diamond of G color and SI1 Clarity. If you move up to a VS1, you will pay approximately an extra $1000 per carat. Move up to VVS1, the increase will be approximately $700 per carat. Improve the clarity to IF and the increase will be approximately $700 per carat.


Round Brilliant	Oval	Marquise	Pear	Heart	Emerald	Trillion	Princess

Cut

The cut of a Diamond is the only property which is totally dependent on man. Although often overlooked, cut is actually one of the most important aspects to consider when choosing your diamond. A Diamond cutter analyzes the rough diamond, and has to determine how to extract the most beauty and most profit out of the rough stone.

Cut refers to not only the shape of the diamonds, but its proportions and finish, factors which determine the sparkle of the diamond.

The goal in terms of extracting the greatest beauty from a Diamond, is to have light enter a Diamond, disperse the light as it bounces inside the Diamond, thereby producing the different colors and sparkly effect, and finally returning as much light to the eye as possible.

According to conventional wisdom, the proportions shown above are the best for maximum light return. The 2-dimensional illustration below shows the theoretical path a ray of light will take through an ideal-cut Diamond. . As you can see, the rays of light entering the Diamond, reflect back to the eye. But it is possible for a diamond cutter to extract more weight out of the diamond by increasing the diameter of the stone. This will make the stone too shallow, and light may escape from the side of the stone, as shown here... or leak out of the bottom of the stone, like here... Another side-effect of this cut, is that it makes the stone appear larger. Don't be fooled by this. The fact that it appears larger than it is does not make it a better stone. If you compare a shallow stone to a well-cut stone, you will see the difference in how the well-cut stone "lights up".

By the same token, it is common to see the opposite problem. A stone which is cut too shallow will "leak out light" in much the same way as the shallow stone. Here are two illustrations . . .
1) and 2) .

This is not to say that a shallow or deep stone is a sign of a poor, or "low-quality" diamond cutter. Sometimes the shape of the rough diamond makes it impractical to cut a stone closer to "ideal" proportions without losing significant weight. But it is important to note the "light leakage" which will result from this cut.

How much does "cut" affect cost?

The effect of all the different properties of Diamond on Cost is discussed in more detail in the Cost section. For cut, it can vary depending on the quality of the Diamond.

Cost

The most important "C" you have to think about is COST.A marketing person whose job it is to sell as many Diamonds as possible. The reality is that there's no "guideline". There are too many personal factors to consider.

Information taken of internet.The information on this webpage is only for information purposes.