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What to consider when shopping for a diamond
Understanding the elements that make up a diamond's grade, alone with the various types of diamond certificates can be immensely helpful when shopping for a diamond.
Four factors go into grading a diamond. These are known as the 4Cs: cut, clarity, color and carat weight. Each 'C' has its own measurement. Put together, the 4Cs help diamond sellers set prices and compare diamonds, and they also help you find a beautiful diamond. The more you understand about the 4Cs, the savvier you'll be in choosing your diamond.More...
A diamond's cut is harder to measure, but it is arguably the most important C. A diamond cutter crafts each diamond to get the most value and beauty. As a prism of light, a diamond can be cut so that light enters and reflects back out to create a brilliant effect. Sometimes diamond cutters may sacrifice this light performance by cutting diamonds to be heavier or look bigger so they cost more, rather than cutting angles and facets that deliver the most light. When shopping for a diamond, be sure to get information on the quality of the cut.More...
The clarity grade is a reminder that a diamond is a thing of nature - and like most natural things, it's rarely perfect. Diamonds often have flaws, known as inclusions and blemishes. Diamond cutters try to cut and polish a diamond to hide these inclusions or work around them, but they're still there - and the clarity grade measures them. The clarity scale ranges from flawless to heavily included.More...
Diamonds come out of the earth in many different colors. Diamond sellers have traditionally valued white diamonds higher than others, and the grading scale reflects that. The D grade, at the top of the scale, is considered 'colorless,' rarest and most expensive. Going down the 23-grade scale from D to Z, diamonds become progressively more yellow, brown or gray.More...
People often think carats stand for size, but they actually measure weight. Diamonds are also measured in smaller units of weight called points: 100 points equals 1 carat. The abbreviation 'ctw' stands for 'carat total weight,' which measures all diamonds in a piece of jewelry. Be sure not to look at carat weight alone when shopping for a diamond: quality matters more.More...
Most diamonds go to a grading lab to be independently evaluated before a store sells them. The report from that evaluation is called a diamond certificate - also known as a diamond grading report, diamond dossier, diamond quality document or diamond light performance certificate. This document gives you most of the important information you need to know to make an informed diamond purchase. File it with your important papers afterward. Because no two diamonds are exactly alike, a diamond certificate can even serve as your diamond's fingerprint or identification in case of loss or theft.More...
Gemological Institute of America (GIA)
GIA pioneered diamond grading in the 1940s, creating a consistent way to describe a diamond in common language. Today, GIA grading certificates are considered the hallmark of integrity in the diamond world. The private laboratory issues two types of reports. The GIA Diamond Grading Report provides scientifically determined information on shape, clarity, color, cut, carat weight, proportions, finish and treatments. It also includes a diagram of the diamond showing any inclusions that affect clarity. The GIA Diamond Dossier® is a more concise version of the full report and is available for loose diamonds between 0.15 and 1.99 carats.More...
International Gemological Institute (IGI)
IGI is an independent grading and appraisal organization with centers in New York City and Los Angeles as well as Antwerp, Bangkok, Mumbai, Tokyo, Dubai and Toronto. Several gemologists analyze each diamond and produce an accurate description of its characteristics, such as color, clarity, carat weight and the quality of its cut. The information is stored in IGI's computer database so you may request an update of your report if the need arises. IGI also offers colored gemstone certificates, educational courses and laser inscription services.More...
Gemological Science International (GSI)
GSI is an independent gemological laboratory based in the heart of New York City's Diamond District with additional offices in diamond centers around the world. GSI offers gemstone identification, grading and appraisal services exclusively to the fine jewelry industry. The lab's business model is built on integrity, innovation, professional service, and shared research education.More...
American Gem Society (AGS)
AGS Laboratories developed the AGS Performance-Based Cut Grading System. The key to the system is tracing light as it travels through the diamond. That's what determines whether a diamond looks bright and lively or dull and mediocre. The lab offers several levels of grading reports. The most popular is the Diamond Quality® Document. It shows cut (if available), color, clarity and carat weight accompanied by a profile showing that individual diamond's measurements along with a custom plot with the actual facet arrangement and inscription details.More...
GemEx Systems Inc.
GemEx is an independent laboratory that focuses on light performance, or the movement of light through the diamond. Trained professionals use the GemEx BrillianceScope® Analyzer to measure a diamond's white light (brilliance), color light (fire) and scintillation (sparkle). These measurements are then compared with those of other diamonds of the same shape (the highest and lowest amount of white light, color light and scintillation possibl for each shape was set by measuring thousands of diamonds). The GemEx Light Performance Report illustrates the measurements for your diamond in a three-bar graph.More...
Need help getting started?
Our educational site, Jewelry Wise, can help you get on the right track. Visit Jewelry Wise »
How do I prioritize the 4cs?
The more you understand about the 4Cs, the savvier you’ll be in choosing your diamond.Learn more about the 4cs »
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