Loose Diamonds: The 4 C’s – Technical Articles

The Four C’s are four variables that are used to calculate the value of a diamond. These include Clarity, Color, Cut and Carat Weight.

CUT

Cut refers to the angles and proportions that a skilled diamond cutter creates in transforming a rough diamond into a polished diamond. These proportions influence the way a diamond displays scintillation, brilliance and fire.

Scintillation describes the flashes of sparkle that appear when light passes over a diamond. Brilliance is the amount of light reflected from a diamond. Fire refers to the way a diamond disperses white light passing though it into the different colors of the rainbow. Well cut diamonds display more scintillation, sparkle and fire than average or poorly cut diamonds, and so command a premium price.

The symmetry and quality of polish are two important factors that affect the cut quality.

Cut also refers to the shape of a diamond. While the round brilliant and princess cut diamonds are today’s most popular shapes, many other fancy shapes are available. These include marquise, pear, oval, emerald, cushion, triangle, baguette, heart shapes and others.

Over 200 fancy shapes are registered with the U.S. Patent and Trademark office. If you’re looking for a special shape please call our diamond experts for assistance.

CARAT WEIGHT

A carat is a unit of mass equal to 0.20 grams (0.1286 pennyweights, 0.007055 avoirdupois ounces). A carat is further subdivided into 100 “points” (0.01 carat = l point). The current definition of a carat was adopted in 1907 at the Fourth General Conference on Weights and Measures held outside Paris. The word carat came to English from French, derived from the Greek kerátion, meaning “fruit of the carob”, via the Arabic word qirat and the Italian word carato. Since carob seeds had a reputation for uniform weight they were often used by ancient gem traders as a balance scale counterweight.

COLOR

Most diamonds fall into a color range between pale yellow or brown known as the normal color range. Fancy color diamonds can be intense yellow or brown in color (somewhat rare) and even pink, blue, purple, green or red (very rare).  The most sought after diamonds are totally colorless and will  command premium prices. White diamonds are discounted in price when more body color is detected, while an intense pink or blue diamond can be among the most expensive. Out of all naturally occurring fancy color diamonds, red diamonds are the rarest and sometimes sell for millions of dollars. The degree to which diamonds exhibit body color is an important part of the 4 C’s used to evaluate all diamonds.

CLARITY

Clarity describes the clearness or purity of a diamond. This is determined by the number, size, nature, and location of the internal (inclusions) and external (blemishes) imperfections.