The Essentials of Diamond Grading

May 7th 2016
Selling Diamonds: Diamond Grading
When you sell diamonds and diamond jewelry, it's essential to know exactly how gemologists grade them. You don't want to pass off inferior diamonds to your customers, and you also don't want to get ripped off by your diamond suppliers. It doesn't take long to pick up the basics of diamond grading, and it serves you well when you want to go to a mineral show and find new suppliers or explain to your customers exactly how a diamond is graded. You don't have to study grading to the point where you instantly pick out the flaws in a diamond, but spending a bit of time to get solid base knowledge in the subject helps you and your business out. Diamonds are graded based on a combination of the 4 Cs. 
The color of a diamond plays heavily into its value. The Gemological Institute of America established the primary diamond grading system used for diamond and jewelry sellers. The first factor that this scale looks at is the color. The color scale starts at D and goes to Z, with the first part of the scale reserved for colorless diamonds. The further down on the scale you go, the more color you see, typically yellow or gray. This color scale only applies when you're grading colorless diamonds, not colored diamonds. Ideally, you want a diamond that has no color inclusions that change it from being crystal clear. 
Many minerals, diamonds included, have inclusions within the body of the stone. These inclusions, which may be chemical inclusions, debris or another mineral, change the clarity of the stone. This grading scale requires a 10X magnifier to determine the severity of the inclusions. The more inclusions you have, the lower the diamond grade. If the jeweler cannot see inclusions at 10X, it's considered a flawless diamond. On the other end of the scale, an L1-13 clarity rating means that the inclusions are so bad that you don't need the magnifying glass to see them in some cases. When inclusions are this prevalent, the structural integrity of the mineral is in question. The overwhelming majority of diamonds mined don't meet even the base requirements necessary to turn them into gemstones. Clarity often ends up being the problem, as the inclusions are simply too much to turn the stones into proper gemstones. 
Carat Weight
Popular culture often depicts large carat weights to directly correlate with the size of the diamond. Despite this misconception, carat correlates to weight, not the size or amount of facets a stone has. One gram is equivalent to five carats. When you measure the carats in a diamond, you divide each carat into a unit that measures 100 points to determine the grading quality of the diamond. The bigger the diamond's carats, the more expensive the gemstone. While you hear about many outrageous wedding rings having massive stones, your general consumer isn't looking for much bigger than a carat or two. Not only is it more affordable and traditional looking, but it's also more practical to wear on a day-to-day basis on a ring. 
The cut is a diamond feature that most people understand for grading. A diamond is cut to emphasize the flashing and sparkle that this mineral possesses. An uncut diamond does not show this type of characteristic. It needs a proper cut to come alive. Out of all of the grading metrics, the cut is the most objective. Some features that a diamond grader looks for in a properly cut stone include how bright the diamond is when it catches the light, whether the diamond has a proper amount of fire with the light refractions and the pattern of refraction across the stone when the light hits it. With time and experience, you can learn the cuts and how well they bring out the inner fire of the diamond. 
Selling diamonds can be a fun and lucrative profession. With a sturdy knowledge base of what makes a diamond valuable, you're on your way to successful selling of these gorgeous stones.

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