When buying a diamond, it is vitally important to know about the 4 C's. They are cut, color, clarity, and carat weight. Together, the 4 C's determine a diamond's value. It is essential to learn about each of the 4 C's before purchasing a diamond because each C speaks differently to each individual. For some, the carat weight is the most important while for others it is the cut.

Cut
To many, cut is the most important of the 4 C's. Each diamond is cut using an exact mathematical formula that unleashes its brilliance and fire. It also refers to the number of facets that the diamond has. The most common cut is the round brilliant. The round brilliant has 58 flat, polished facets that reflect the maximum amount of light. The mathematical formula also takes into account the depth of the cut. If a diamond is cut too shallow or too deep it will lose some of its fire. A well-cut diamond will reflect the light and refract it back out to your eye. Cut is not to be confused with shape.

Color
While diamonds come in every color of the spectrum, the most valuable diamond color is colorless. Truly colorless diamonds are extremely rare and as a result are expensive. They are graded on a color scale established by the Gemological Institute of America (GIA). Diamonds range from D (colorless) to Z. The further down in the alphabet the diamond is, the more yellow it appears. Color can best be determined by looking at a loose diamond on a pure white surface, and by noting any contrast.

Carat
Some people believe that carat refers to the size of a diamond while in actuality; carat is the term used to measure a diamond's weight. A carat is equal to 200 milligrams, and there are 142 carats to an ounce. One carat is made up of one hundred points. The larger the diamond, the greater its rarity. Because larger diamonds are more rare, they generally have a greater value per carat.

Clarity
Internal imperfections and external irregularities affect the clarity of the diamond by interfering with the passage of light throughout the stone. Imperfections such as spots, lines, or bubbles are known as inclusions. The diamond is more valuable when it has fewer inclusions. According to the GIA's quality analysis system, clarity is graded on a scale ranging from flawless (FL or IF) to imperfect (I). The system is based on the visibility of inclusions at a magnification of 10x.

While these are the 4 most recognized C's, a fifth and less recognized, yet equally important C does exist. That is Confidence. Confidence in your jeweler is extremely important when buying this piece of jewelry that will last forever, and be passed down among generations. It is important to shop at a professional jeweler, one that is a member of a professional trade association such as Jewelers of America (JA). JA requires high ethical standards of its members and provides them with ongoing education.