Cut
Key Takeaways:

-It is a diamond's most important characteristic, as it has the greatest influence on a diamond's brilliance.

-It is the measure of a diamond's light performance which delivers its sparkle.

Illustration of Diamond Cut


Illustration of diamond cut


Most gemologists will agree that, of all the four C's, cut is the most important. The cut of a diamond influences the way it reflects light, which in turn determines its brilliance. Even a diamond with perfect color and clarity may appear lifeless if it does not have a good cut.

In a well-cut diamond, light enters the stone and is reflected around the mirror-like facets before exiting through the top, or table. This careful orchestration of the movement of light inside the stone and back to the eye is what causes the fiery sparkle we recognize as brilliance. A skilled professional can maximize this effect by cutting a diamond to very precise proportions. Too shallow a cut will allow light to escape through the bottom of the stone, causing it to look dull. Too deep a cut will cause light to be lost through the diamond's sides, making it appear dark.

Depth is not the only important factor; other angles and proportions matter as well. In fact diamond cutters now use sophisticated computer modeling tools to give them a full picture of how light will behave inside a stone, allowing them to adjust proportions to optimize a diamond's brilliance, as well as its brightness, scintillation, and fire, the qualities known collectively as the diamond's "face-up appearance."

Some round diamonds come with certifications that supply their cut grade. The GIA (Gemological Institute of America) ranks diamonds as Excellent, Very Good, Good, or Fair. The AGS (American Gem Society) ranks them as Ideal, Excellent, Very Good, Good, or Fair. Amazon represents both Round GIA "Excellent cut" diamonds and Round AGS "Ideal cut" diamonds as "Ideal" on our site, since these two terms both refer to the highest quality of diamond cut.

Round cut diamonds, it should be noted, are the only ones that can achieve a grading of "Ideal." Other cuts, such as Princess, Asscher, or Emerald, will receive, at the highest, a grading of "Very Good." For diamonds that do not have AGS or GIA certifications, Amazon will calculate the cut based on the stone's depth, table percentages, symmetry and polish.

Ideal

A diamond described as Ideal represents the highest standards of cut, with only the top 3% of all diamonds falling in this category. An Ideal Cut diamond reflects nearly all the light that enters it and displays maximum brilliance and fire. For those who want the very best that money can buy, this is the cut to choose.

Very Good

A diamond described as Very Good reflects nearly as much light as an Ideal cut diamond, and represents approximately the top 15% of diamonds based on cut. The proportions may overlap with many of the proportions of an Ideal cut, with slight variations from the preferred range that allow the cutter to create a larger stone. A diamond with a Very Good cut has exceptional brilliance and is generally priced slightly lower than an Ideal cut diamond.

Good

A diamond described as Good reflects most of the light that enters it, and is much less expensive than a Very Good cut. A diamond in this category represents roughly the top 25% of diamonds based on cut. Its proportions may vary from the preferred range because the cutter has opted to maximize the size of the stone rather than creating a smaller Very Good quality diamond. For those shopping on a budget, a diamond in this range offers good quality and excellent value.

Fair

A diamond described as Fair represents the top 35% of diamonds based on cut. Though it is still a quality cut, it reflects less light and displays less brilliance than a Good Cut diamond. Diamonds in this range are typically cut to maximize size over other factors.


Clarity
Key Takeaways:

-Clarity is the grading of a diamonds presence or absence of inclusions.

-The greater a diamond’s clarify, the greater its brilliance and value.


No two diamonds are alike. A diamond's most distinguishing characteristics are its inclusions, marks that are often invisible to the naked eye. However, under a jeweler's magnifying loupe or microscope they can look like crystals, tiny rivers, or clouds. A diamond's clarity is determined by the presence or absence of inclusions--fewer inclusions mean better clarity—and how visible they are. The greater a diamond's clarity, the greater its brilliance and value. A diamond categorized as internally flawless will have no inclusions, but this is extremely rare.

Diamonds with very, very small inclusions are graded as VVS1 or VVS2. Those with larger inclusions are considered lower-grade. Diamonds with inclusions that are visible with the naked eye are graded I1 to I2.

Diamond Clarity


Illustration of clarity


Color
Key Takeaways:

-Traditional diamonds range from colorless to light yellow with colorless being considered the most valuable.


Though diamonds come in a wide range of colors, colorless diamonds have traditionally been considered the most valuable. Most diamonds are graded on a scale using the letters of the alphabet, from D (colorless), the best grade, through Z (a light yellow). It is difficult for the untrained eye to notice such variations in color unless stones are being compared side by side. The comparatively rare colored diamonds are known as fancy-colored and are also quite valuable. They range in hue from the more common yellow (also graded Z+ on the alphabetic scale) to pink, blue, brown, champagne, red, and even black and white.

Diamond Color Scale


Illustration of color


Diamonds that are graded D, E, and F tend to be the most expensive because of their rarity. However, any diamond you buy should have a good balance of cut, color, and clarity, so as to impart the most brilliance and dazzle possible.


Carat
Key Takeaways:

-A diamond’s weight, and size, is measured in carats with diamond stones often being more highly valued.


Carat Weight


Illustration of carat weight


A diamond's weight is measured in carats, with one carat being equivalent to 100 points. You will often see a diamond referred to as a 3/4-carat stone or a 75-point diamond. Larger stones are often more highly valued, but size should not be the only consideration--high brilliance, which varies according to clarity, cut, and color grade, is highly desirable in a diamond. The diamond carat weight or carat total weight listed is approximate. Variances may be up to .05 carats.


Shape

Gem Shape Grid


Illustration of diamond shapes


The traditional round cut provides a combination of the best qualities a diamond can have. However, there are other shapes that can emphasize a diamond's different features. The choice of a shape is best based on personal taste and the design of the jewelry.


Setting

Diamonds can be set in a variety of different ways in order to create different jewelry styles:

Prong Setting

Prong-settings are most-popularly used in jewelry with either 4 or 6 prongs per setting. This type can be used on a variety of stone shapes and facets and allows for maximum exposure of the shape for brilliant light and sparkle.

V Prong Setting

A popular setting for princess-cut diamonds, it features a notch carved into each prong that squeezes against both sides of the stone for a secure hold.

Bezel Setting

This setting creates a modern look, securing the diamond deep inside the mounting. The surrounding metal is pushed over the edges of the stone to secure it in place. It can be used on any stone shape.

Channel Setting

Stones are aligned side by side within the grove the jewelry silhouette. Most often found with round, princess, emerald and baguette-shaped diamonds, they are secured by hammering the sides of the channel walls towards the stones.

Pave Setting

Small openings within the surface create a flush finish for diamonds on a pave setting. The stones are secured by overlapping gem spurs that create a bead-like finish over the stones.

Tension Setting

This modern setting uses the hardness of the metal to hold the stone on place. Small grooves are cut into the end of the metal for a secure grip.

Bar Setting

Stones are nestled in grooves between bars in this modern setting. A hammering allows the metal to overlap the stones, holding them in place.


Shopping for an engagement ring? Learn about popular ring style settings in our Engagement Ring Guide.


Care

Diamonds, as the hardest substance on earth, are resistant to damage. However, diamond jewelry is set in different metals, and care will vary from piece to piece. The girdle can be chipped by a hard blow, making a protective setting extremely important. Diamonds should be cleaned in a solution of one part ammonia to six parts water, using a gentle scrubbing brush to remove any dirt. It is a good idea to have them cleaned once a year by a professional jeweler, at which time the security of the setting can be checked as well. Diamond jewelry should be stored in a soft cloth pouch to ensure that the stone will not scratch other jewelry.

Colored Diamonds

Colored diamonds often receive special treatement to preserve their rich hue and require special care. Common treatments for diamonds are:

Black Diamonds: Heat-Treated

Blue Diamonds: Heat-Treated or Irradiated


Certification

A diamond certificate represents independent verification that the stone purchased has all the qualities of cut, color, clarity, shape, and weight expected. It is a further indication of the condition and value of that diamond as represented on our site. Such certificates are issued by several agencies employing highly trained gemologists and provide an unbiased and accurate evaluation of the diamond. These gemologists scrutinize each stone to analyze its dimensions, clarity, cut, color, finish, symmetry, and other details.

Diamonds shipped from and sold by Amazon.com may be certified by the American Gem Society Laboratories (www.agslab.com), the Gemological Institute of America (www.gia.org), or the International Gemological Institute (www.igiworldwide.com). The type of certificate provided will be noted in the product specifications of your jewelry purchase; if you do not see a certificate type noted, one will not be provided.


Our Diamond Policy

Amazon.com sources high-quality diamonds from some of the world's largest suppliers. All our diamond suppliers certify that to their best knowledge their product does not originate from conflict countries or other sources with links to criminal or terrorist activities. Only diamonds meeting our exacting criteria will make it into a finished piece of jewelry. The diamond carat weight or carat total weight listed is approximate. Variances may be up to .05 carats.


More Questions?

Our diamond experts are on call Monday through Friday from 9 a.m. to 9 p.m. Central time, and Saturday through Sunday from 10 a.m. to 7 p.m. Call them toll-free at 1-866-423-5356.