Refers to a diamond’s facets. According to the American Gem Society, proportions, light interaction and finish are all important factors in a diamond’s cut. Cut is primarily about the craftsmanship of the diamond itself rather than the shape and setting. The better cut a diamond, the more sparkle and brilliance it will have.
Can actually be found in any diamond. From blues and reds to pinks and yellows, colored diamonds are the easiest to find. However colorless diamonds, such as those for wedding rings, are the rarest to find and have the highest value as a result. These diamonds receive a rating on a spectrum from colorless to yellow. Color follows cut in importance level.
Looks at a diamond’s natural flaws. If it’s an internal flaw it is called and “inclusion.” If it’s an external one, it is called a “blemish.” The size of the inclusions or blemishes can vary in size and each affect the value and grading of the diamond. Like color, diamonds without inclusions and blemishes are rare and possess a higher value.
Refers to a diamond’s weight. “One carat equals 0.200 grams or 1/5 gram and is subdivided into 100 points,” according to the American Gem Society. The more carats a diamond possesses, the more it will cost since larger diamonds are rarer. However, the cut, color and clarity of the diamond can affect the weight and value of a diamond.
The 5th C, also known as Certification, could be the most important when making your diamond investment. It should be a non-bias report from a grading lab providing important information about the 4 C's of the diamond. Note, that Certification is different than an Appraisal. An Appraisal assigns a monetary value to your diamond or piece of jewelry, which will be needed for insurance purposes.