Learn How to Use the IGS Gem Price Guide
Table of Contents:
- How to Use the IGS Gem Price Guide
- Gemstone Properties
The IGS Gem Price Guide covers commonly traded colored gemstones as well as more unusual, collectible gems. The values listed are based on a variety of sources, including primary and secondary gemstone dealers, jewelers, miners, and wholesale suppliers.
How to Use the IGS Gem Price Guide
A faceted gem’s price is based on an evaluation of its physical and optical properties. These are often referred to as the “Four Cs” — color, clarity, cut, and carat. (Here’s a handy introduction to how gemologists grade those properties).
However, despite well-established grading systems for color, clarity, and cut, any evaluation of these properties is inherently subjective. Even gemologists and appraisers may disagree about the quality of a specific stone, so disagreements regarding gem prices do occur.
Ultimately, the price of a gem is what one willing buyer and one willing seller can actually agree upon. Our gem price guide is just that — a guide. Keep in mind that gems are sold outside these price ranges every day. See our article on pricing faceted gems for more information.
Prices listed are retail in US dollars. Wholesale is generally one third of retail. High-end gems are often marked up 30% or less, while low-priced, more “commercial quality” faceted gems are often marked up considerably more.
Unless otherwise noted, all prices listed below are for cut gems, not rough or raw crystal forms, and all weights are in carats.
If you’re not familiar with gem grading or pricing, consider getting an appraisal before buying or selling a gemstone. However, bear in mind that there are no regulations governing who can appraise gems, so carefully review the credentials of prospective appraisers. Choose an appraiser from a well-respected gemological organization or a reputable gem trader with experience dealing in the specific gem you’re interested in.
Many of the gems listed below have color descriptions. Some just have simple color names — red, purple, etc. Others also have codes with abbreviations and numbers, such as “slpR 5/5.” See Spinel, for example. Those codes are gem color grades from the Gemological Institute of America (GIA) color grading system. For a brief explanation of the codes, read this article. Consult our article on gemstone color grading for more information.
Some of the gems listed below have clarity descriptions such as “clean” or “eye clean.” Other gems have coded clarity grades, such as “VVS” and “SI/I.” See Emerald and Sapphire, for example. For a brief explanation of the GIA clarity codes, read this article. For more detailed information, consult our article on clarity types and grades for colored gemstones.
Colored gemstone cutting can be difficult to evaluate, but its effects will be apparent to your eyes and your wallet. Consult our article on evaluating the cut for more information.
Some of the gem values listed below distinguish between faceted and cabbed stones. Others refer to specific types of faceted gem cuts, such as rounds, ovals, pears, etc. This overview of the lapidary arts will introduce you to the basic types of gem cutting — faceting, cabbing, tumbling, and carving. To learn more about specific faceted cuts, see our articles on fancy gem cuts and cutting styles.
One carat equals 0.20 grams. Unlike the other Cs, carats can be objectively measured and confirmed.
Note that some gems have increases in prices per carat at specific weights. Some gems actually see a decrease in price per carat as they get larger. To learn about gem weight and value, check out our article on carats and gem grading.