Understanding Diamond Quality

Fine diamond jewelry is always admired and desired for its beauty. For centuries, diamonds, regarded as the ultimate gift, have been a symbol of eternal love and beauty as defined by the wearer. Whether a gift for yourself or someone special, diamond jewelry is special.

Lisa Robin Jewelry Diamond Hoop Earrings

Not all diamonds are created equal. I like to think of diamonds as children, each one is unique. Diamonds come in many sizes, shapes, colors, and with unique internal characteristics, but like children, each polished diamond is valuable and should be cherished. A diamonds value is based on a combination of factors and one of those factors is rarity. Diamonds with certain qualities are more rare and thus more valuable than diamonds those without them.

Natural Diamonds

Mined diamonds are formed deep beneath the Earth's crust. Once created and then forced upward from the center of the Earth until uncovered. This is the traditional diamond. This wonder of nature is one of the reasons diamonds are so admired and valued. But before this process was understood, many ancient civilizations believed that these beautiful shimmering stones were the embodiment of lightning on Earth. Old legends tell tales of great healing powers of diamonds curing brain disease, alleviating pituitary gland disorders, and drawing toxins out from the blood.

Natural Diamond

Lab Created Diamonds

Considered the sustainable diamond, lab created diamonds, lab grown diamonds, or man made diamonds, they’re all one and the same. Lab created diamonds are carbon diamonds that have been grown in a laboratory. Much like flowers in a greenhouse, lab created diamonds are grown above earth under controlled conditions. This new source of diamonds “grows” diamonds identical to diamonds extracted from below earth - chemically, physically, and optically. They are as real as diamonds pulled from the earth, and they sparkle just as brilliantly.

Lab created diamonds are distinctly eco-friendlier and sustainable. There's no harmful water or air pollution due to growing diamonds nor is any ecosystem uprooted during the lifetime of a lab created diamond. Mined natural diamonds inherently displace earth, dredge oceans, and destroy habitats.

Scientists and all diamond grading laboratories have subjected lab created diamonds to rigorous testing and studies to determine that diamonds from above earth are identical to those from under the earth. Diamonds, whether grown below or above earth, are made of pure carbon containing only SP3 type carbon bonds (tetrahedral bonds) in the cubic crystal structure. 

Virtual Diamond Vault

I offer both natural or "standard" diamonds and lab created (grown) diamonds. The virtual vault contains thousands of diamonds in all shapes and quality. By simply selecting criteria you can easily search the virtual vault to compare quality and pricing so you can make the best buying decision.

Virtual Diamond Vault Lisa Robin Jewelry

The 4 C's

To make the most of your diamond jewelry budget, it helps to understand how diamond quality is determined. Today, the 4C's of Diamond Quality is the universal method for assessing the quality of any diamond, natural or lab created, anywhere in the world. This standard values perfection in a diamond. It wasn't until the 1930's that the Gemological Institute of America (GIA) created the first, and now globally accepted standard for describing diamonds: Color, Clarity, Cut, and Carat Weight.


Of all the 4Cs, the diamond cut has the most significant effect on a diamond's brilliance; this means it will be less luminous if it is poorly cut. The more precise the cut of the diamond, the more captivating the diamond is to the eye. Cut does not refer to shape (pear, oval), but the symmetry, proportioning and polish of a diamond.

There are three "ideal cuts" commonly used as standards to compare a more or less symmetrical arrangement of facets, which together modify the shape and appearance of a diamond crystal to enhance its beauty best. The most popular of diamond cuts is the modern round brilliant, which uses both mathematical and empirical analysis to perfect its facet arrangements and proportions.

A diamond's cut is evaluated by trained graders, with higher grades given to stones whose symmetry and proportions most closely match the particular "ideal" used as a benchmark. In determining the quality of the cut, a diamond grader is evaluating the craftsman's skill. During the diamond cutting process, the diamond cutter wants to get the heaviest diamond out of a rough stone because diamonds are valued in part by weight. Sometimes the desire for heaviest weight and ideal cut can be at odds lowering cut grade.

New technologies like laser cutting and computer-aided design, have not only enabled the development of cuts whose complexity, optical performance, and waste reduction was not possible before, but also allowed for unique shapes such as stars and butterflies.

The GIA Cut Grading System applies to the most popular cutting style – the modern round brilliant – and all clarities across the D-to-Z color range. There are five cut grades: Excellent (EX), Very Good (VG), Good (G), Fair (F), and Poor (P). 

Brilliant Cut Diamonds

Cut does not refer to shape, but the symmetry, proportioning and polish of a diamond. There are three "ideal cuts" commonly used as standards to compare a more or less symmetrical arrangement of facets, which together modify the shape and appearance of a diamond crystal to enhance its beauty best. The most popular of diamond cuts is the modern round brilliant.

A brilliant round cut is exceptionally good at reflecting white light, which is a factor when choosing a white diamond. Most fancy colored diamonds are not cut into brilliant round because the essential characteristic in a fancy colored diamond is its color, not its ability to reflect white light.

Cuts derived from the brilliant round, referred to as fancy cuts, come in a variety of shapes. Most fancy cuts fall into four categories, which include marquise, heart, triangular trillion (also trillian or trilliant), oval, and the pear. Step cuts are the rectangular cuts like emerald or Asscher, and mixed cuts are the princess cut diamonds.

Diamond Cuts


The color of gem-quality diamonds occurs in many hues. In the range from colorless to light yellow or light brown. Colorless diamonds are the rarest. A chemically pure and structurally perfect diamond is entirely transparent with no hue or color. However, in reality, almost no gem-sized natural diamonds are perfect.

Most natural diamonds fall in a normal color range between white and pale yellow or brown. The grading scale for diamonds in the normal color range used by internationally recognized laboratories is from D, which is colorless to Z, which is a pale yellow or brown color. Traditionally, diamonds that possess a pale yellow or brown hue, are the least desirable for jewelry but that has changed. Diamonds in brown shades are stylish and called champagne, cognac, and chocolate diamonds. Diamonds of more intense color (usually yellow but in some cases red, green, or blue) are called fancy color diamonds.

On the Gemological Institute of America's scale are valued according to their clarity and color. Grades "D" or "E" are considered colorless and is much more valuable than an "R" or "Y" rated diamond, which is light yellow or brown. Supply and demand establish the value. High color diamonds are rarer, and consumers more desire bright white appearance.

When buying a diamond, near-colorless grade diamond ("G" or "H" rated) is more cost-effective than purchasing a colorless grade diamond ("D" rated). If compared, they are nearly indistinguishable to the naked untrained eye, especially when mounted on a ring setting.

Other natural colors (blue, red, pink, for example) are known as "fancy," and their color grading is different from white colorless diamonds. 

Diamond Color

Other natural colors (blue, red, pink, for example) are known as "fancy," and their color grading is different from white colorless diamonds. 


Diamond clarity is the quality that relates to the existence and visual appearance of internal characteristics of a diamond called inclusions, and surface defects, called blemishes. Diamonds without inclusions or blemishes are rare; however, requiring magnification to see.

Inclusions are solids, liquids, or gases that were trapped in a mineral as it formed. They may be crystals of a foreign material or even another diamond crystal or may have produced structural imperfections, such as tiny cracks that make a diamond appear whitish or cloudy. The appearance of the stone is affected by the number of inclusions, their size, location, and how visible they are. Most inclusions present in gem-quality diamonds do not modify the diamonds' performance or structural integrity and are not visible to the naked eyes. However, large clouds can affect a diamond's ability to transmit and scatter light. Large cracks close to or breaking the surface may reduce a diamond's resistance to fracture. 

Diamond Clarity


Carat is a measure of physical weight in metric carats and is the most objective grade of the 4Cs. One carat equals 1/5 gram and is divided into 100 units, called points. For example, a half-carat gemstone would weigh .50 ct. or 50 points. Carat is not a measure of size.

Understanding diamond weight is one of the biggest and easiest ways to reduce costs when buying diamond jewelry. The price per carat increases as the weight goes up. Especially when shopping for larger diamonds, consider going under the commonly sought out weight. If you are looking for a 1 carat diamond, consider searching for a carat weight just below the 1 carat weight for example, 0.95carat. If you were looking for half a carat then consider 0.45ct.