How to Rate a Diamond

Rate a diamond based on the four Cs.

Diamonds, which are one of the most expensive gemstones due to their high quality and unbreakable status, are also very desirable. When rating a diamond, most jewelers insist on using the four Cs, which are cut, color, clarity and carat. Each category affects the value of a diamond. A flawless diamond will have perfect color, cut and clarity but the carat can vary. You can find a flawless 1 carat diamond or a flawless 2 carat diamond. It's best to work with a professional when rating a diamond, as they have been trained to notice all possible flaws.

Things You'll Need

• 10x magnification glass

Instructions

1. Look at the cut of the diamond. Cut refers to how a diamond is shaped and polished. The cut is done by a professional to bring out the high quality of the gem from the rough stone. The diamond should be cut in a way that allows the maximum quantity of light to be reflected.

2. Check the diamond's color. Color varies in a diamond. The best quality of diamond should be completely colorless. Diamonds are still valuable when they have hints of color but it is very light. Letter grades are given to judge the color of the diamond. D means the diamond has no color and E through Z each have increasing levels of light hues. Z is actually a valuable diamond since it has so much yellow that it is considered a yellow diamond, rather than a regular diamond with a yellow hue. There are distinctively colored diamonds, such as pink or blue diamonds, which are very rare and are not rated on the same scale.

3. Inspect the clarity of the diamond. Clarity determines the amount of inclusions, or internal defects, in the diamond. The clarity should usually be judged by a jeweler or other trained professional who knows what to look for. Diamond clarity is checked with a 10x magnification to look for inclusions. Inclusions can include tiny cracks, other diamond crystals within the diamond or crystals of a different material. Most diamonds, (about 80 percent) have a low clarity, which only allows them to be used industrially. The other 20 percent are considered gemstones. The diamonds are more expensive when they have a high clarity. A flawless diamond is the most valuable.

4. Determine the carat of the diamond. Carat is the weight that determines a diamond's mass. The higher the carat, the more valuable the diamond. However, most diamonds increase in value at milestone weights, such as 0.5 carats, 1 carat or 2 carats. Even though a 0.35 carat diamond would have a higher mass than a 0.2 carat diamond, the difference in price would be slight. This is because neither diamond has reached a milestone carat.

References

• "Jewelry Savvy: What Every Jewelry Wearer Should Know"; Cynthia A. Sliwa, Caroline Stanley and Haelyn Lee; 2007
• "Before You Buy an Engagement Ring: With a 4-Step Guide for Making the Right Choice (Schiffer Book)"; Nancy N. Schiffer; 1999
• "Gemstones (Smithsonian Handbooks)"; Cally Hall; 2002
• "Gemstone Buying Guide, Second Edition: How to Evaluate, Identify, Select & Care for Colored Gems"; Renee Newman and Ren'e Newman; 2003