Before purchasing a big-ticket item, many consumers will spend hours researching their options and reading reviews and ratings to determine the best balance of cost and quality. When it comes to buying a diamond, however, you may not be familiar with how the stones are evaluated. What is the truth about diamond ratings?
Diamond Ratings Are Determined By Independent Agencies
The stones are reviewed by third-party agencies with internationally-recognized systems. The Gemological Institute of America (GIA) rating system is generally recognized as the industry standard, and is the one with which most consumers are most likely to have some familiarity.
A Rating Is Not the Same As An Appraisal
Diamond ratings are scientific evaluations of the primary characteristics that determine a stone's quality; they are not appraisals of monetary value. They do, however, relate to value and cost -- the higher the rating, the more valuable the stone is considered and, subsequently, the higher its price is likely to be.
Diamond Ratings Are Based on Science
Quality reports grade diamonds on the four Cs: carat, cut, color, and clarity. Each category is graded on a scale with defined standards.
A carat is equal to 200 milligrams or 0.2 grams. This unit of measurement identifies a diamond's weight.
While many people think the term "cut" refers to the stone's shape (such as round, square, pear, or emerald), it actually identifies how a diamond reflects light. The cut gives the diamond its brightness, or brilliance. A diamond that is well-cut has angles and a finish that reflect light around the diamond and back up through its face (known as the table). A stone with a poor cut loses light out of the sides and bottom of the diamond, leaving less light reflecting back to the eye, which makes the diamond less brilliant. Numerical formulae have been calculated to maximize brilliance, identifying optimal diamond proportions such as depth to diameter.
The color of a diamond is the result of its composition. The more colorless the diamond, the more light can pass through it and the more sparkle it will emit. The GIA color scale identifies colorless stones with the highest rating of D. The more yellowish or brownish color a stone has, the further down the alphabet the grades fall, all the way to Z. The truth about diamond ratings is that even diamonds graded G through I will appear virtually colorless to the naked eye.
Clarity refers to flaws on the surface of a diamond or within it. A diamond doesn't have to be identified as Flawless to appear that way to the naked eye; only those at the low end of the rating scale will have visible flaws without magnification.
Diamond quality reports serve as useful guides to help consumers consider cost and quality based on a set of internationally-recognized standards. However, the truth about diamond ratings is that even stones that don't earn the highest grades in every category can still be stunning.
If you enjoyed this article, be sure to check out How to Select the Right Diamond Carat