Diamond Fundamentals

Diamond FundamentalsDiamond Shapes

The 4 C's

You already know that the “Four Cs” are Color, Clarity, Cut, and Color. Learn more about color grading here, then click on the diamond above for information about the other C’s.

Diamond Shape

The traditional round cut, when executed to the ideal proportions, maximizes a stone’s natural beauty by yielding the fullest sparkle, fire and brilliance. However, a variety of other cuts are popular and often incorporated into our designs.

Diamond Dictionary

Do you have questions about diamonds and their terminology?  We have answers.  Click on the diamond icon above to learn everything you’ve always wanted to know about girl’s best friend.

How to Read a GIA Diamond Grading Report

A diamond certificate is a document issued by a gemological laboratory, which describes, as objectively as possible, a number of physical characteristics of a loose diamond.  If you’d like to learn more about how to understand your GIA report, click the diamond icon above.

Color

A diamond’s color is graded on an alphabetical scale from D-Z to describe how much or how little color a diamond possesses. With very few exceptions, diamonds that are graded as colorless are considered to be the most valuable. Truly colorless stones, graded D, are extremely rare and very valuable.

D-F: Colorless, perfect or almost perfect color.

G-J: Near colorless, good to very good color. This diamond may “face up” colorless when mounted.

K-M: Light but noticeable yellow or brown tint. May “face up” near colorless when mounted, especially when mounted in yellow gold.

While many diamonds appear colorless, or white, they may actually have subtle yellow or brown tones that can be detected when comparing diamonds side by side. Diamonds were formed under intense heat and pressure, and traces of other elements may have been incorporated into their atomic structure accounting for the variances in color. A single change in color grade can significantly affect a diamond’s value. Although the presence of color makes a diamond less rare and valuable, some diamonds come out of the ground in vivid “fancy” colors–well-defined reds, blues, pinks, greens, and bright yellows. These are highly prized and extremely rare.

color

Clarity

Clarity is an indication of a diamond’s purity. It is the term used to describe quite literally the clearness or lack of flaws in a diamond. All diamonds have some, naturally occurring marks in them, which may or may not be visible to the naked eye. These are known as imperfections or inclusions. In all diamonds, except the most rare, tiny traces of minerals, gasses, or other elements were trapped inside during the crystallization process. These are called inclusions, but are more like birthmarks. They are called this because they are “included” in the diamond! They may look like tiny crystals, clouds, or feathers and they’re what make each diamond different and unique. Many of these birthmarks are not visible to the naked eye. In fact, it is very rare to find a diamond that is completely clean to the expert eye using magnification. The clarity of a diamond is graded by how many, how big and how visible the inclusions are. The fewer and smaller the inclusions, the more rare and valuable the diamond. Less than 1% of all diamonds ever found have had no inclusions and can be called internally flawless (IF).

The following are abbreviations for terms that are used world wide to describe the clarity of a diamond:

IF,V VS1,V VS2: Internally flawless or near flawless. Impossible to extremely difficult to find any inclusions, even under 10x magnification. IF is Internally Flawless, and VVS1 and VVS2 are “Very, very slightly included”.

VS1,VS2: 100% clean to the naked eye, and moderately difficult to very difficult to find inclusions with 10x magnification. VS1 and VS2 are “Very slightly included”.

SI1SI2SI3: Should be completely to almost completely clear to the naked eye (eye clean) when viewed from the top. Fairly easy to find imperfections with 10x magnification. SI diamonds are “Slightly included”.

I1I2I3: Borderline “eye clean” to fairly easy to find imperfections with the naked eye. Very easy to find imperfections with 10x magnification. I1 through I3 diamonds are said to be “included”.

clarity

Cut

This is one of the most important of all characteristics, and among the hardest to judge. All other factors being equal, a poorly cut diamond can be worth less than half the value of a well “made” stone. The proportions of a stone as well as its polish and precision of faceting determine how much of the diamond’s potential fire and beauty may be released.

Diamond cutters are paid to retain the maximum weight from rough stones. You will find poorly cut diamonds such as overly long or fat Marquises, extremely deep Heart Shapes and Emerald Cuts, and Ovals and Pear Shapes with big shoulders, or overly deep or out of shape Rounds.

A poorly made stone tends to result in a higher yield (less waste) from the rough while a better made diamond “wastes” more of the rough. A well cut round diamond typically weighs only about 40% or less of the original weight of the piece of rough the cutter started with. This is why better cut diamonds and near ideal cut stones command a premium.

The way a diamond is cut will most certainly influence its sparkle, fire and brilliance, as well as its perceived size and even, to some degree its apparent color. In order to maximize the diamond’s brilliance it must be cut in a geometrically precise manner. This means properly aligning the facets so light will enter the diamond and reflect back through the large top facet, or table of the diamond.

Below is a diagram of the proportions of the Ideal Cut for maximum brilliance. Symmetry, polish, and faceting are the most noticeable features of cut, but also important are percentages for depth, height and angles. Light should enter and exit a diamond through the top facets. A cut that is too shallow or too deep reflects it through the bottom facets, and lets the light “leak” out of the bottom or side of the gem.

idcutdiagram

An Ideal Cut diamond, which is round when viewed from above in its setting, tends to be more beautiful than other diamond cuts, as its proportions maximize the stone’s sparkle, fire and brilliance.

Among the other popular diamond shapes are the Marquise, Emerald, Princess, Oval, Trilliant, Pear and Heart cuts. While these alternative shapes are fashionable, and often vital to the design of a piece of jewelry, you should expect to see a decrease in the brilliance that is yielded by an Ideal Cut diamond of similar quality.

Carat

The standard unit of measure for diamonds and other gemstones is the carat.

One carat is equal to 1/5 of a gram, or 1/142 of an ounce. The carat is also referred to as containing 100 “points”. Therefore, a 50-point diamond weighs ½½ carat, a 25-point diamond weighs ¼¼ carat, and so on. The price per carat of diamonds can at times increase exponentially with size, due to the rarity of larger gemstones. A one-carat diamond typically costs 3.5 to 4 times what an equivalent ½½ carat costs, and the same goes for subsequent increases in size.

carat

Diamond Shapes

Round or Brilliant

 

Pear

 

Trilliant

 

Princess

 

Marquis

 

Heart

 

Emerald

 

Oval

 

Diamond Dictionary

Blemish
The degree to which a diamond is free from inclusions, graded on a scale from Flawless to I3. There are 12 grades in total .

Brilliance
Along with life, sparkle, scintillation, refraction and dispersion, a word used to describe the reflective and refractive properties of a diamond.

Carat
Standard unit of measure for diamonds and other gemstones. One carat is equal to 1/5 of a gram, 1/142 of an ounce, or 100 points.ClarityThe degree to which a diamond is free from inclusions, graded on a scale from Internally Flawless to Included. There are 10 grades in total.

Clarity
EnhancementSee “drilling” and “fracture filling”.

Cleavage
An internal imperfection which runs in the direction of the grain of the diamond. It sometimes extends to the surface of the diamond, or is “healed” inside the diamond .

Cloud
A cluster of microscopic white or crystalline inclusions or pinpoints inside a diamond .

Color
The best color is no color or “colorless”. Most diamonds have some greater or lesser degree of yellow or brown color, sometimes so slight that it is virtually imperceptible. Some rare diamonds have very intense or exotic colors (pink, blue, green, purple, or even red) and can be extraordinarily valuable .

Color Enhancement
Laboratory processes ranging from a simple coating or “painting” as it is known in the trade to sophisticated permanent alteration of the presence of certain trace elements found in the naturally occurring diamond. Laboratory certification is your best protection against treated stones.

Culet
The bottom most facet or point of a diamond. The culet of some round diamonds may be so pointed they are considered to not be a facet at all .

Cut
Cut refers to two main aspects, first: the shape of the stone i.e., emerald cut, princess cut etc. second, the proportions and dimensions of a diamond also known as “make”.

Depth
The distance between the culet (bottom) and the table (top) of the diamond, measured in millimeters. Given as a percentage of the average diameter of a diamond.

Depth Percentage
The depth of the diamond divided by the average width.

Drilling
A man-made enhancement process in which a laser is used to drill to the inside of a diamond to an inclusion, which is then bleached to appear white. Ashford.com does not offer any laser drilled diamonds for sale.

EGL
European Gemological Laboratory. Widely respected in the trade offering independently grading certificates.

Eye-clean
Free of any internal inclusions or external blemishes to the naked eye, when viewed from the top.

Facets
The polished planes (surfaces) on the surface of the diamond, defining its dimensions.

Feather
A common naturally occurring white feather shaped inclusion, which is not visible to the naked eye .

Fire
Along with life, sparkle, scintillation, refraction, and dispersion, a word used to describe the brilliance of a diamond.

Fluorescence
Also known as photoluminescence, the property some diamonds have that makes them glow a certain color (usually blue) when placed in an ultraviolet rich environment. Strong, very strong and sometimes medium blue fluorescence may slightly improve the color appearance of diamonds rated “H” in color or below (I,J,K etc). Such fluorescence in some of the “lower” colors may even enhance the value of these stones. Strong blue fluorescence in diamonds D to F color may impart a very slightly bluish appearance and may, in turn, detract a few percent from the value of those diamonds. Some diamonds with strong blue fluorescence can have a hazy or “milky” appearance. Ashford.com buyers are very careful to avoid purchase of such stones .

Fracture
An internal or external imperfection which may have developed three million years ago or last week as a result of trauma (usually a hard impact) .

Fracture Filling
A man-made enhancement process in which an inclusion is injected with filler material to mask the presence of it.

GIA
Gemological Institute of America, the single most widely accepted diamond authority. An independent, third-party grading service offering diamond grading certificates .

Girdle
The outermost edge of a diamond, it can be unpolished, polished, or faceted. Usually where the diamond is held in a setting.

I1
A term used to describe the clarity of the diamond, meaning Included. There are three grades in the I range: I1, I2 and I3.

I2
A term used to describe the clarity of the diamond, slightly more included than I1. There are three grades in the I range: I1, I2 and I3 .

I3
A term used to describe the clarity of the diamond, slightly more included than I2. There are three grades in the I range: I1, I2 and I3 .

IF
Internally flawless. Free of any internal imperfections at 10 power magnification .

Inclusion
A naturally occurring imperfection often referred to as a feather, pinpoint or cloud in the diamond that may or may not be visible to the naked eye.MakeThe proportions and dimensions of a diamond, also known as cut.

Melee
Diamonds which weigh less than 1/5 of a carat (20 points) are known as melee. They are usually side diamonds or accent diamonds in a larger piece of jewelry.

Natural
An external characteristic on or near a diamond’s girdle, a natural is actually an unpolished portion of the “skin” of the rough diamond.

Pavillion
The faceted portion of the diamond which is below the girdle.PinpointA very small inclusion inside a diamond.

Point
A unit of weight measure equal to 1/100 of a carat. A 1/2 carat diamond weighs 50 points, etc.PolishThe overall uniformity of the polish of a diamond. Graded from poor to excellent, it is based on the final finish applied to the facets and facet junctions by the cutter.

SI1
A term used to describe the clarity of the diamond, meaning slight inclusions. The GIA recognizes two grades in the SI range: SI1 and SI2. The EGL recognizes a third SI grade, SI3. Well cut diamonds in the SI range should be completely to nearly eye clean.

SI2
A term used to describe the clarity of the diamond, meaning slight inclusions. The GIA recognizes two grades in the SI range: SI1 and SI2. The EGL recognizes a third SI grade, SI3.SI3A term used to describe the clarity of the diamond, meaning slight inclusions. The GIA recognizes two grades in the SI range: SI1 and SI2. The EGL recognizes a third SI grade, SI3.

Solitaire
A single diamond set in a mounting which shows off the simplicity and elegance of the diamond.

Sparkle
Along with life, fire, scintillation, refraction, dispersion, a word used to describe the brilliance of a diamond.

Symmetry
The overall uniformity of the cut of a diamond. Graded from poor to excellent, it is based on the diamond’s proportions and the relation of one facet to another.

Table
The top and largest facet of a diamond, it is where much of its light both enters and exits the diamond .

Table Percentage
A measurement which relates the width of the table divided by the total top surface of area .

VS1
A term used to describe the clarity of the diamond, meaning very slight inclusions. There are two grades in the VS range: VS1 and VS2. The imperfections in VS stones can be quite difficult to find even with the aid of 10 power magnification.

VS2
A term used to describe the clarity of the diamond, meaning very slight inclusions. There are two grades in the VS range: VS1 and VS2. The imperfections in VS stones can be quite difficult to find even with the aid of 10 power magnification.

VVS1
A term used to describe the clarity of the diamond, meaning very, very slight inclusions. There are two grades in the VVS range: VVS1 and VVS2. Imperfections in VVS stones should be extremely difficult to find even with the aid of 10 power magnification.

VVS2
A term used to describe the clarity of the diamond, meaning very, very slight inclusions. There are two grades in the VVS range: VVS1 and VVS2. Imperfections in VVS stones should be extremely difficult to find even with the aid of 10 power magnification.

How to read a GIA Diamond Grading Report

A diamond certificate is a document issued by a gemological laboratory, which describes, as objectively as possible, a number of physical characteristics of a loose diamond. A diamond described by such a certificate is said to be “certified.”

The Gemological Institute of America (GIA) Gem Trade Laboratory has literally set the industry standard for diamond grading and gemological identification. In 1953, GIA created the international diamond grading system, which is the standard recognized by virtually every professional jeweler and diamond broker in the world.

Today, the GIA Diamond Grading Report™ serves as the international gem and jewelry industry’s benchmark credential. GIA Diamond Grading Reports are regarded throughout the gem and jewelry industry worldwide as the hallmark of integrity, reliability, and consistency in diamond grading.

1. GIA Diamond Grading Report

This is where you can find the GIA laser inscribed identification number, as well as the diamond’s shape and cutting style (round brilliant or emerald step cut, for example) and its dimensions in millimeters.

2. Grading Results

A breakdown of the diamonds 4Cs: Cut, Color, Clarity and Carat. **TIP: Currently, GIA only provides a cut grade for round brilliant diamonds.

3. Additional Grading Information

Information on polish, symmetry, fluorescence, and any inscriptions or additional comments.

4. Proportion Diagram

A map of the diamond’s actual proportions that includes depth, table, girdle, and culet.

5. Clarity Characteristics

This is where you’ll find the diamond’s clarity plot, an approximate map of the number, size, type, and position of its grade-setting inclusions as viewed under a microscope.

What is the difference between a Diamond Certificate and an Appraisal?

A Diamond Certificate is a document issued by a Gemological Laboratory describing a loose diamond. The laboratory will not issue certificates on diamonds that are set in a mounting. A Diamond Certificate issues a “grade” indicating the physical properties of the diamond “at the time of evaluation,” and retains its accuracy, and value to the purchaser, over a long period of time, assuming the diamond does not chip or is not otherwise altered.

An appraisal can be performed on a loose diamond, a mounted stone, or a piece of jewelry. If the stone is not loose, the physical properties are estimated using various estimating techniques. Most importantly, an appraisal indicates the dollar value of the piece under consideration, most often for insurance purposes, and that value can change considerably over time.

Many people make the mistake of using an in-house appraiser to evaluate the purchase price of their diamond. This is a mistake, for several reasons. First, appraisals are often over-estimated, and are therefore a poor gauge of a diamond’s value or price. Equally important, in-house jewelers may often be biased.

To further complicate matters, many people have become more educated when it comes to buying diamonds, and have learned the importance of having a GIA certificate. What they have not learned, unfortunately, is how to differentiate between a GIA GTL (Gem Trade Lab) Grader and a GIA G.G. or Graduate Gemologist. Many assume that getting an appraisal by a GIA gemologist is the same as getting a GIA Certificate. Some unscrupulous jewelers further that illusion in their dealings with customers.

The GTL (Gem Trade Lab) Grader is a GIA employee who performs the diamond grading for the Gemological Institute of America. A GIA Graduate Gemologist, on the other hand, has simply passed the GIA Diamonds and Colored Stone course.

The GTL Grader is far better trained in grading and usually has far more experience than a Graduate Gemologist. Further, the GTL Grader does not have the same vested interest in the outcome of the grade of the stone being evaluated.

Contact Galatea Today

See a shape that you desire? Call Galatea for prices on certified diamonds today!

(205) 879-3045

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