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Diamonds are among nature’s most precious and beautiful creations.
Color
Colorless diamonds are scarce—most diamonds have tints of yellow or brown.
4Cs
Factors used to describe diamonds: Clarity, Color, Cut, Carat Weight
Rarity
The rarity of one or more of the 4Cs can affect value.
Octahedron
The crystal shape of a gem diamond is often the octahedron.
Trigons
Trigons—little triangular depressions—occur only on octahedral faces.
Growth marks
Diamond’s growth marks help experts separate diamonds from simulants.
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See gem as
- Polished
- Rough
Buyer's Guide
Few consumer products undergo the scrutiny that diamonds are subjected to. That’s because subtle variations in color, cut and clarity can cause significant differences in a diamond’s value.
How to Choose a Diamond
FIND A JEWELER
Use your zip code to find a jeweler near you with GIA reports and GIA-trained staff.
FIND A REPORT
Verify the information on your report matches what is archived in the GIA report database.
What To Look For
Color: The amount of a diamond's color, on a scale of D-to-Z
GIA’s D-to-Z scale measures the colorlessness of a diamond, comparing it to masterstones under controlled viewing conditions.
Clarity: The relative absence of inclusions and blemishes
Clarity grades are based on the number, size, relief, and positions of inclusions that can be seen under 10x magnification.
Cut: Can affect diamonds’ brilliance, fire, scintillation
Precise workmanship is required to cut a diamond so its proportions, symmetry, and polish maximize brightness, scintillation, and fire.
Carat Weight: Diamonds are sold by weight
One carat is equal to 0.20 grams. Only one in 1,000 diamonds weighs more than a carat.
Diamond Quality Factors: The Comprehensive Guide
Read Article
Tips & Advice
1. Insist on a diamond grading report.
The differences in diamond quality can be so subtle even a trained jeweler can't recognize them without lab verification. Insist that any diamond you buy comes with an indisputable verification of its quality from an unbiased source.
2. Protect your purchase.
Have your diamond appraised and insured. Appraisers and insurers rely on diamond grading reports to accurately evaluate the value of gems. As an additional measure, consider having your diamond laser-inscribed with its GIA report number, to provide verification if it is ever lost or stolen.
3. Look for a gem that weighs a bit less than your target size.
Prices per carat generally increase as the weight passes “magic numbers” such as 1.00, 1.50, and 2.00 carats. A diamond that weighs 0.95 carat will cost less per carat than a 1.00 carat stone but look almost the same.
- View Sample Report
- About Diamond Reports
- 4Cs Blog
- How to buy Diamonds Online
Questions & Answers
Q
How do I get a GIA grading report?
A
You can send your diamond to GIA for grading and analysis. Many consumers send the diamond through a retailer for packaging, shipping and insuring the item. A jeweler will have to remove your diamond from its setting, since GIA Diamond Grading Reports are only issued for unmounted stones.
Q
Are diamonds with a higher number of facets brighter?
A
The number of facets affects the pattern of the reflections in a diamond rather than overall brightness. Diamonds with more facets have numerous smaller reflections instead of fewer larger reflections. Brightness is a function of proportions, polish and symmetry, not the number of facets.
Q
How can I be sure a diamond is conflict-free?
A
In 2002, a coalition of governments, non-governmental organizations and the diamond industry established the Kimberley Process to control the export and import of rough diamonds to eliminate the trade in conflict diamonds. Today 99% of diamonds in the marketplace are conflict-free.
Q
Does GIA grade diamond cut?
A
Yes. The GIA Diamond Cut Grading System, introduced in 2005 after years of extensive research, assigns one of five grades to describe the overall cut quality of a standard round brilliant diamond in the GIA D-to-Z color range.
Q
How can I be sure that a GIA grading report is authentic?
A
All GIA reports contain security features such as a hologram, security screen and microprint lines that prevent them from being forged or duplicated. Also, GIA’s Report Check service can verify whether the information on the report matches what’s contained in our database.
Q
Will GIA appraise my diamond?
A
Although GIA does not perform appraisals, a GIA laboratory report does independently confirm the quality characteristics that determine value. While GIA can't recommend an individual appraiser,there are several appraisal associationsand networks that can help you locate one in your area.
Q
Does GIA grade laboratory-grown diamonds?
A
Yes. GIA has been grading laboratory-grown diamonds since 2007. Beginning July 1, 2019, GIA Laboratory-Grown Diamond Reports and identification reports no longer use the term “synthetic.” The GIA Laboratory-Grown Diamond Report includes the standard GIA color, clarity and cut grading scales for reference purposes. The reports use descriptive terms to identify color and clarity. The LGDR, LGDR-Colored Diamond and LGDR-Colored Diamond Report Color Identification reports will include a statement that identifies the type of growth process used, CVD (Chemical Vapor Deposition) or HPHT (High Pressure High Temperature), and will indicate if there is evidence of post-growth treatments to change the color.
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Caring for Your Diamond
Keep your diamond beautiful by following simple care and cleaning guidelines.
Durability
Sudden and extreme temperature changes are threatening to a diamond’s stability.
Care and Cleaning
A safe way to clean diamond jewelry is to use warm water with a mild soap and a toothbrush.
Treatment
Diamond color and clarity treatments can be affected by heat and chemicals.
Find out more
Diamond: The Complete Guide to Caring for Your Diamond
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