The name “diamond” comes from the ancient Greek word adamas (“invincible”). Gem-quality diamonds are rare. They are crystals formed deep in the earth under conditions of extreme high temperature and pressure. Once it was believed that it took eons for the earth to create a diamond. Now we recognize that diamond creation deep within the earth can occur in months, or even weeks. After formation, it takes millions of years for nature to bring them close enough to the surface of the earth for mining.

Many consider diamonds to be the most valuable and beautiful of all precious stones. The diamond itself is the hardest and most durable of all known materials. Diamonds receive the highest grade of 10 on Mohr’s Scale of Hardness. All other known substances receive lesser scores. Whether considered a “girl’s best friend”, the “elite level” of membership, or the “promise of love”, a diamond brings a level of beauty and sophistication that surpasses all others.

Diamonds were first mined in India over 2,500 years ago. They quickly became associated with divinity, and were believed to bring good fortune to those who owned them. Ownership of rare colored diamonds was restricted to kings.

Today, approximately half of all diamonds originate in Africa. Significant deposits have been discovered in Canada, India, Russia, Brazil, and Australia. About 130 million carats (26,000 kg) are mined annually. Most of these are low-grade stones. High quality diamonds are rare. Diamonds are generally mined from deep in the Earth where the high pressure and temperature form the stones from carbon crystals

The “4 Cs” that that determine the quality of a diamond affect not just cost but also appearance and durability. (The “4 Cs” represent: color, clarity, cut and carat [weight]).

The 4 C’s of Diamonds

The Four Cs : Clarity

Clarity is a term used to describe either the absence or presence of “clarity characteristics” (called inclusions) inside or on the surface of a diamond. Tiny surface blemishes or internal inclusions — even those seen only under magnification with a jeweler’s loupe — can alter the brilliance of the diamond and, thus, affect its value. Most flaws that exist in jewelry grade diamonds cannot be seen without looking at gemstones through a jeweler’s magnifying loupe. Inclusions that are usually identified under 10x magnification are often so minimal that they these stones are referred to as “eye clean”. An “eye clean” diamond is defined as one with no inclusion visible to normal, unmagnified vision. Clarity is defined by a numbering and lettering system. Levels begin with Flawless (F & IF) and move down to Very Very Slight (VVS1 & 2), Very Slight (VS1 & 2), Slightly Included (SL1 & 2), and Included (I1, 2 & 3).

Flawless: No internal or external flaws

Very, Very Slightly Included: Very difficult to see inclusions with 10x magnification

VS1, VS2
Very Slightly Included: Inclusions are not typically visible to the unaided eye

SI1, SI2
Slightly Included: Inclusions are visible under 10x magnification and may be visible with the unaided eye

I1, I2, I3
Included: Inclusions are visible with the unaided eye

The Four Cs : Cut

A diamond’s cut does not refer to its shape but to the gemstone’s proportions. The depth, width and uniformity of its facets determine the brilliance, durability and other qualities looked for in a diamond. Diamonds are cut into many different shapes. Quality of the rough diamond and current style determine the diamond cut. The most popular shapes are Round, Oval, Square, Princess, Emerald, Baguette, and Marquise cuts.

Once cut, the diamond’s overall proportions, as well as placement of its many reflective facets, will play a large role in its beauty. The consistency and balance of the cut can greatly affect how the stone captures light and reflects it back

Cut can be described in a number of ways. At The Charles Collection, we use the standard diamond laboratory method of reporting. The dimensions of the diamond are recorded. This will determine whether a particular diamond falls under the grading system of: Ideal, Excellent, Very Good, Good, or Fair.

When the cut of a diamond is IDEAL, all the light rays entering from the top are reflected back through the top in a blaze of light.

In a diamond that is cut too deep, much of the light is reflected out the side at the wrong angle and results in a less brilliant appearance. The diamond may appear black in the center.

In a diamond cut too shallow, light “leaks”through the bottom and the eye may see a dull reflection in the diamond. This diamond will also look less brilliant. Many buyers choose diamonds of a shallow cut to make the diamond “appear” larger than it truly is.

What is an IDEAL Cut Diamond?

In 1919, Marcel Tolkowsky after analyzing the proportions for round brilliant cut diamonds wrote a Masters thesis on their dimensions. These measurements have become the basis for what is now known as the “Ideal Cut Diamond.” This Ideal cut is a mathematical formula for cutting diamonds to precise angles and proportions to gain the optimal reflection and refraction of light.

Names of the dimensions of a diamond

An “Ideal Cut”, “Premium Cut” or “Modern Round Brilliant” (Tolkowsky Round Brilliant) diamond as shown in the diagrams above would have the following basic proportions according to the AGS:

  • Table Size: 53% to 57% of the diameter
  • Total Depth: 58% to 63% of diameter
  • Crown Angle: 34 to 35.5 degrees
  • Pavilion Depth: 42.5% to 43.5%
  • Girdle Thickness: medium to slightly thick
  • Culet: pointed, very small to small
Ideal Cut vs. Standard Cut Diamond

When deciding how to cut a rough diamond, a cutter must make a cost-benefit analysis as to how to maximize the cut stone’s value. Often, a rough diamond is cut into an octahedron to make two diamonds to maximize its value. If a cutter prefers to maximize carat weight, he will make standard cut diamonds. The cutter may also make an Ideal cut diamond at the expense of carat weight to produce a more brilliant stone.

Ideal Cut

Standard (Premium) Cut

Rough Diamond Material Loss

Finished Stones

Cutting Time

Crown Symmetry

Pavilion Symmetry

Girdle Symmetry

Greater Loss

Lower Carat Weight

2 to 6 days




Less Loss

Higher Carat Weight

1 to 3 Days

Shallow Crown

Deep Pavilion

Thick Girdle

The Four Cs : Carat

Carat weight affects both a diamond’s appearance and its price. The size of a diamond is measured by weight in carats. One carat is equal to approximately 0.2 grams. The weight of a diamond may also be referred to in points. A point is equal to 1/100 of a carat. A 75-point diamond equals 0.75 carat. Some incorrectly believe that all diamonds of the same carat weight would be the same size. This is not the case. The size of a diamond is affected by its outside dimensions. These proportions of height, width, and depth will vary in a stone of the same weight. A “deep” 2 carat diamond may not appear as large as a “shallow” 1.75 carat diamond. Because of rarity, larger carat weight diamonds of gem quality are much more valuable.

The Four Cs : Color

Diamonds are often thought of as colorless.Like many gemstones formed with traces of other minerals, diamonds of striking color can result. These unusual diamonds can be blue, yellow, red, brown, pale green, pink, or violet. Because of their rarity, colored diamonds are considered extremely valuable and may cost many times the price of a similar “colorless” stone. At The Charles Collection, we offer colorless, yellow, blue and pink Diamonds.

Colorless diamonds of greatest value are those with the least color. Completely colorless diamonds are extremely rare. These diamonds are referred to as white diamonds. All other colorless diamonds are judged against white diamonds. Some diamonds have a fluorescence, which makes them glow under ultra violet or “black” light. The color scale for transparent diamonds runs from D-F (colorless), G-J (near colorless), K-L (faint yellow), to Z (light yellow).

Qualities not included in “The Four Cs” which affect the value or appearance of a diamond include physical characteristics such as fluorescence (light emission), as well as its history – including its source and which gemological institute performed evaluation services on the diamond.

A clean diamond is more brilliant and fiery than the same diamond when it is “dirty.” Even a thin film absorbs some light that could have been reflected to the person looking at the diamond. Colored dye or smudges can affect the perceived color of a diamond.The current practice is to thoroughly clean a diamond before grading its color.

A diamond’s beauty is determined by its shine, sparkle, and the light it emits. The diamond’s certification should be considered when evaluating its purchase. Of the four “C”s, carat weight and cut are mathematically defined, however, clarity and color are matters of human judgment and as such they can be open to interpretation. The Charles Collection carries certificates from the following gemological associations.

  • Gemological Institute of America (GIA)
  • American Gemological Society (AGS)
  • International Gemological Laboratory (IGL)
  • European Gemological Laboratory USA (EGLUSA)


Round Brilliant Diamonds
This shape accounts for over 75% of diamonds sold. Its cut is calibrated to achieve the maximum fire and brilliance.

Oval Diamonds
This evenly proportioned, elongated shape gives a flattering illusion of length to the hand.

Marquise Diamonds
A drawn out shape with pointed ends named Marquise because it was inspired by the smile of the Marquise de Pompadour. Similar to the oval cut, creates the illusion of longer fingers.

Pear Shaped Diamonds
This cut combines the oval and the marquise. It is shaped like a teardrop. It belongs to that category of diamond whose design most complements a hand with small or average-length fingers.

Heart Shaped Diamonds
The ultimate symbol of romance is the heart shaped diamond.

Emerald Cut Diamond
The Emerald Cut is a rectangular shape with cut corners. Imperfections can be more pronounced in this cut. Only a superior stone should be used for an emerald cut.

Princess Cut Diamond
This square or rectangular cut has many facets. It is a relatively new cut which flatters long fingers.

Trilliant Diamonds
This cut may be a sharp triangular shape with pointed corners or a more rounded triangular shape with many facets.

Radiant Diamonds
This square or rectangular cut combines the elegance of the emerald cut with the brilliance of the round cut. The many facets maximize the effect of its color refraction.