No two diamonds are alike. That is why each one endures a rigorous grading process before it is allowed to be sold. Expert gemologists carefully examine each one, and understanding this process is important to ensuring that you know exactly what you're purchasing.

Grading Procedure

The detailed examination of each diamond starts with a grading procedure. The Gemological Institute of America (GIA) puts their diamonds through a specific process to get the most accurate grade possible.

Expert gemologists begin their examination in the appropriate viewing area, which is tightly controlled with perfect lighting and viewing conditions. This step involves finding and documenting anything that is on or in the diamond.

After the initial viewing, the diamond is sent to a lab in a blank case that includes no information about it. This ensures that it is graded consistently and objectively. This begins the long process of lab testing that is required to certify a diamond.

The results of lab testing and information gathered from the initial viewing are compiled and summarized in a grading report, which will have a certifiable GIA report number for verification. Some diamonds may have their number laser-inscribed on them upon purchase, and if your diamond doesn’t, then we recommend getting the inscription. This ensures the diamond's verification in case it’s ever lost or stolen.

What Happens in the Labs?

First, the diamond is checked to see if it is synthetic (lab grown) or if it is natural. If it is synthetic, it goes through an entirely different procedure. For now, we will follow the path of a natural diamond to break down the process of evaluating and grading each of the 4Cs (color, clarity, cut, and carat).


Unlike other grading systems that might rate a jewel on the presence of color, diamonds are graded on the absence of color. The more colorless the diamond, the higher its quality, therefore giving it a higher grade. In the Gemological Institute of America (GIA), the color grade is based on a master set of diamonds that represent each color grade on the GIA color scale. The color scale is based on the letters from D to Z, with D representing the complete absence of color and Z representing the darkest yellow or brown color that could appear in a diamond. Anything closer to the D grade has a higher quality than anything closer to the Z grade.


Clarity measures a diamond's flaws or imperfections. Each diamond is carefully examined by the naked eye, under 10x magnification, and microscopes. Any imperfections are reported and described in a detailed plot, which then goes into the unique certification report.

The scale ranges from flawless (under 10x magnification there were no blemishes or flaws) to I3 (shows flaws under 10x magnification, microscope, or naked eye). The diamond is also placed under testing to see if it was treated to improve its clarity or if it was not treated in any way.


Cut refers to the amount of light that is released through a diamond, not just its basic shape. Gemological Institute of America (GIA) places their diamonds on a scale used for round brilliant cut diamonds.

EXCELLENT Even patterns of bright and dark areas.
VERY GOOD Increased darkness in the mains with a splintery pattern, and slightly darker within the table of the diamond.
GOOD Dark mains and a slightly dark ring around the table edge.
FAIR Lack of contrast and overall general darkness. The table edge and the upper girdle area are very dark.
POOR Complete darkness inside the diamond.
The cut of a diamond affects its brightness, sparkle, and how it unleashes its light. Therefore, the cut determines 50% of a diamond’s price. During the cut evaluation process, the diamond is placed on a highly precise measuring device that turns it 360 degrees. This is where the final cut grade is determined by taking hundreds of measurements, including: proportions, cubic size, polish and symmetry, and girdle size.


Carat refers to a diamond's weight. The diamond is placed in a special chamber on a highly precise electronic scale. It is weighed, and the scale will go up to the fifth decimal place (.09672). While the weight is referred to as carats, each carat can refer to 200 mg or 1/5 gram. Each carat can be subdivided into points for more precise measurements where they are rounded to the hundredth decimal place (.10). Each 1 carat is equal to 100 points.


Fluorescence refers to the soft-colored glow (most commonly blue) that appears when a diamond is placed in or around black or ultraviolet light. There are four levels used to grade fluorescence.

NONE Excellent:  No fluorescence was detected in the diamond.
FAINT ExcellentVery Good: Very little fluorescence was detected in the diamond – commonly shows as a very faint blue.
MEDIUM Very Good – Good: Fluorescence was detected in the diamondthis commonly shows as blue.
STRONG Very GoodFair: A strong amount of fluorescence was detected in the diamondthis commonly shows as a strong blue. Make sure to ask if the amount affects the appearance of the stone and ensure that there is a return policy available.
VERY STRONG GoodPoor: A very strong amount of fluorescence was detected in the diamondthis commonly shows as a very strong blue. Make sure to ask if the amount affects the appearance of the stone and ensure that there is a return policy available.
A diamond's fluorescence grade will influence its price. The more fluorescence detected, the more of a discount you will receive. Fluorescence can make a diamond look cloudy or give it a yellowish tint.

Compiling the Report

After all information has been gathered, it is summarized in a grading report declaring the diamond’s attributes and official quality. Each report comes with a report number unique to each diamond, which can be laser-inscribed into the diamond. A price is then determined using this report, and the rarer the diamond’s qualities are, the higher the price tag will be.

Remember, beauty does not always indicate quality, so make sure to look at the grading report. It gives you more to work with than, “Oh, it’s so beautiful!”

Calculating Your Price

Each diamond is priced per carat. So, let’s say a diamond’s report grade declares it equal to $1,400 per carat, and the diamond you're looking at is .50 carat. You want to take the $1,400 and multiply your .50 carat ($1,400 x .50 = $700). Easy enough, right? But what if you’re looking at a diamond that is 1.5 carats? It would be the same calculation: $1,400 x 1.5 = $2,100.

Where to Find the Prices

There is an easy way to pinpoint the price of a diamond: Rapaport. The organization was founded by Martin Rapaport in 1978 and releases a list of prices every Friday. Sometimes it stays the same week-by-week, because diamond prices do not always fluctuate. The list compares worldwide prices and checks for the availability and market conditions in which diamonds are being sold.

There are multiple charts with different size categories. Each chart includes color and clarity grades to produce a number.

(1.00-1.49 CT.)
D 207 165 144 121 107 82 69 58 47 27 13
E 157 143 117 107 95 79 66 56 45 26 16
F 133 120 107 98 86 76 63 54 44 25 15
G 110 105 95 86 79 71 59 52 42 24 15
H 89 87 81 76 72 65 56 49 40 23 14
I 76 74 69 67 64 60 52 46 36 22 13
J 62 60 59 57 55 51 47 41 32 20 13
K 51 49 47 45 43 41 39 35 30 18 12
L 46 44 43 41 39 36 34 32 28 17 11
M 41 39 37 36 34 32 29 27 25 16 11
For example, if you have a 1.25 carat diamond with G and I2 grades, the chart will give you 24. Then you multiply it by 100 to get your dollar total: $2,400. Then, multiply by 1.25 for a total of $3000.

Sweet Spots in Pricing

We all like to save money. But just as importantly, we also like to get quality, even if it means paying a little bit extra. Stay focused on the diamond's characteristics. It is unwise to pay a lot more just for color, especially with the price difference between color categories. Pay close attention to those prices, and remember, those listed are before any discounts kick in.

T Discounts

Diamonds with fluorescence come with a price discount. The higher the fluorescence level, the more of a discount you'll receive. For example, if you have a diamond with a G color grade, an IF clarity grade, and a Very Strong fluorescence grade, you can get a 10% discount.

D - F
-10 to -15%
-7 to -10%
-3 to -7%
VS1 - VS2
-6 to -10%
-3 to -5%
-1 to -2%
SI1 - I3
0 to -3%
0 to -1%
0% 0%
G - H
-7 to -10%
-5 to -7%
-1 to -3%
VS1 - VS2
-3 to -5%
-2 to -3%
0 to -2%
SI1 - I3
0% 0% 0% 0%
I - M
IF - I3
0 to +2%
0 to +2%
0 to +2%
So, referring to the above chart, you can multiply the $2,400 price by your discount. Take your 10% and turn it into a decimal, then move the decimal over two places to the left, giving you .10. $2,400 X .10 = $240. Subtract the $240 from $2,400. $2,400 – 240 = $2,160 as your discounted price.

Help is Here

If you have any questions, CONTACT US! We are available to help you. Buying a diamond blindly could cost you money. Do your research and and purchase a certified diamond from a reputable source.

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