Many jewelers now offer the option of purchasing loose diamonds to be set into an engagement ring or wedding ring setting. This allows you to “build” the perfect ring for yourself or your bride-to-be. Diamonds are graded by leading gem laboratories such as the Gemological Institute of American (GIA) and the European Gemological Laboratory (EGL USA) based on the four Cs: Cut, Color, Clarity, and Carat. Read on for tips on purchasing loose diamonds using the four Cs.
Cut is often considered the most important of the four Cs. This is because the cut of a diamond determines its brilliance (the amount of light reflected). When rough diamonds are mined, they emerge in a wide variety of shapes and sizes. Highly skilled diamond cutters then cut and polish these stones to remove flaws and inclusions (tiny particles) – ideally taking out as many as possible while still preserving as much of the diamond retaining its brilliance. If a diamond’s cut is too shallow, the light that enters the diamond will leak out of the bottom. If a diamond’s cut is too deep, the light will reflect out of the side. An “ideal” cut will reflect the maximum amount of light through the top of the diamond – created a radiant sparkle that travels straight back to the viewer’s eye.
A critical factor in the cut of a diamond is symmetry – the alignment of its many facets (or surfaces) in relation to one another. If the diamond has been cut properly, the light that enters the stone will bounce from facet to facet before reflecting back to your eye. This gives the diamond maximum brilliance. A classic round brilliant shape diamond cut includes 58 facets, and every single one must be positioned in perfect geometric relation to the others.
Diamonds come in a surprisingly wide array of colors (yellows, blues, greens, and reds). However, the most valuable white diamonds are completely clear (“colorless”); others may contain a slight yellow tint. White diamonds are graded on an alphabetical scale from “D” to “Z”. A diamond with a grade of “D” is completely colorless (and very rare). As diamonds move closer to the “Z” grade, they begin to display more of a yellow tint.
Most diamonds contain a few minor flaws or “inclusions” that affect their clarity. An inclusion is any spot, scratch, bubble, or line that occurred when the diamond was still being formed deep in the earth.
Most inclusions are not visible to the naked eye, so gem laboratories use a magnifying glass (at 10x magnification) to determine the amount, size, position, nature, and color of the inclusions. The clarity of diamonds ranges from “flawless” to “included.”
You should avoid diamonds with visible flaws that affect their overall beauty or durability, but it is not necessary to select a flawless diamond. To make sure that your diamond has no visible flaws, we recommend stones with a grade of SI2 or higher. However, some SI diamonds can provide great value as many are virtually flawless to the naked eye.
Carat refers to the diamond’s size and weight. This word is often confused with “karat,” a completely different term used to describe the quality of gold. The price of diamonds rises as their size and weight increase. Therefore, a two carat diamond can cost four times as much as a one carat diamond of the same quality.
By using the four Cs you can ensure you have received the best loose diamond for your money. Make sure to ask your jeweler questions regarding the Cut, Color, Clarity, and Carat when you go out looking for loose diamonds.