Professional Gemological Identification Services
The Accredited Gem Lab® (AGL) designation means the firm you are shopping with has the minimum equipment required to perform gemological testing and appraisals. The equipment includes a gemological darkfield binocular microscope (essential for gemological observations), a master color grading set per American Gem Society (AGS) Standards (for reliable color comparisons of diamonds), a gemological library of reference materials, and more.
Firms with the Accredited Gem Lab® designation prove to their customers and clients they are vested in the thorough inspection of gemstones and jewelry. More importantly, each Accredited Gem Lab® is required to have an AGS titleholder on staff, with a minimum of a Certified Gemologist® (CG) or Certified Gemologist® Appraiser (CGA) title to oversee its use. This ensures that a fully-credentialed gemologist with the proper knowledge is responsible for gemological testing and appraising.
If you are in the jewelry industry and would like to learn more about how to qualify for an AGL designation, please click on the sections below or contact firstname.lastname@example.org.
The American Gem Society (AGS) Gemological Sciences Committee is dedicated to keeping the Accredited Gem Lab® (AGL) designation relevant, which helps support the AGS mission of consumer protection, ongoing education, and a high standard of business ethics. As a result, the requirements to qualify as an AGS Accredited Gem Lab® are currently being reviewed and updated. Please note that these requirements must be met by a Retail or ICGA firm member holding, or applying for the AGL designation:
It is also recommended, but not required that the firm have:
An Accredited Gem Lab® is subject to audit without notice for compliance for the above elements. If the audit identifies noncompliant elements, the titleholder that oversees the AGL (AGL Contact) will have two years from the date of notice of noncompliance to bring the AGL back to good standing.
The following outlines the requirements for the AGS Color Master Diamond Comparator Set for the Accredited Gem Lab® (AGL) designation.
Color: The first diamond must be 0.0 (D), 0.5 (E) or 1.0 (F). Each additional diamond can be no greater than one (1) numerical AGS color grade variation from the previous diamond. For example, if the first color master diamond is an AGS 0.5 (E), the next diamond must be an AGS 1.0 (F) or AGS 1.5 (G). Single or split grades may be assigned according to the Colorimeter Conversion Table under “Grading Results”.
Fluorescence: Master diamonds must not have visible fluorescence. Since fluorescent diamonds can vary in color grades between daylight and artificial light, they are not appropriate color masters. In colors lower than AGS 3.5 (K), faint fluorescence may be accepted.
Cut: Diamonds should conform to the same general proportions. The difference in the appearance of the color of a shallow diamond and a deep diamond, due to the additional depth of the latter, make accurate comparisons more difficult. All diamonds in the set should be of approximately the same size and proportions.
Clarity: Slightly included diamonds are acceptable, providing that the characteristics do not affect the color or transparency of the diamond.
Weight: Diamonds must weigh 0.30 carats or more and must be unmounted. This size is adequate for comparison of diamonds up to 1.00 carat.
Girdle: Diamonds must have polished or faceted girdles and there should not be large girdle thickness variations from one stone to another.
Laser Inscription: Each Color Master Diamond will be laser inscribed with the AGS number, estimated Colorimeter value, and the equivalent master color grade.
The following equipment from the ASSURE Directory of Diamond Verification Instruments will qualify for the Accredited Gem Lab® designation:
Instruments under $10,000
Instruments over $10,000
Sherlock Holmes Device
AMS2 (melee only)
M-Screen+ (melee only)