Fire Agate Gemstone Grading by Fire Agate US | Gem Quality Guide
Fire Agate gemstone quality standards have never really been developed and there are only very generic and loose terms such as Commercial, Imperial, Killer, AAA and Gem quality grading terms being used in an attempt to describe the quality of the stone. Unfortunately these terms are very subjective with no real good standards set in place. In our opinion the lack of any good gem grading standards has been one of the factors which has been hindering the advancement of fire agates in the mainstream gemstone market.
Fire Agates deserve the same as any other gemstone and so we are developing an alphabetical style grading system with 'AAA' being the best (fyi, there are very few of these top end stones and most are in private collections) and 'D' being the lowest grade stone. It will take time to properly delevop and adopt a grading system that is 100% reliable, but at least it will be helpful in specifying some of the factors that we consider make up a high quality fire agate gemstone and assist you in evaluating our stones.
Buying Fire Agate Gemstones online can be very challenging, so do your best in researching and asking questions so that you have a good sense of what you are purchasing. Online
photos can be very deceiving when it comes to gem size, color, brightness and being able to discern any flaws or imperfections. Look for sellers who offer a money back guarantee so that
you can return your purchase if you are not pleased with the stone when you see it in person.
Fire Agate Gemstone Grading Factors (this page is under development) |
Fire Agate US gem grades are based off of a weighted point system. This system includes these factors: Color (# colors represented, color tone, fire type), Cut (quality of craftsmanship, polish/finish, overall shape and usability of stone, % of stone surface with fire display), Refraction (how much light it takes to 'fire up', brightness), Aspect (how well the fire displays from different viewing aspects), Size (weight factor, very large quality gems are scarcer), Unique Factors (sagenite sprays, inclusions), Flaws (cracks, areas of no fire). Available grades are D, DD, DDD, C, CC, CCC, B, BB, BBB, A, AA, AAA.
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Color - Colors represented, % of respective colors, color tone...(ruby red instead of orange-red for example), depth of color.
Grading Points: 0-20, Weighting Factor: 20%
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Refraction - Strength, how much light it takes to 'fire up', brightness, intensity, clarity, intensity of reflection.
Grading Points: 0-20, Weighting Factor: 20%
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Aspect - The way the bands lay and angle of brown out if any. Does the gem display well from different viewing aspects?
Grading Points: 0-10, Weighting Factor: 10%
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Cut - Quality of craftsmanship, overall shape and usability of stone. % of stone surface with fire display
Grading Points: 0-15, Weighting Factor: 15%
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Carat - Weight factor, very large quality gems are scarce.
Grading Points: 0-10, Weighting Factor: 10%
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Special Factors - Sagenite spray, inclusions, unique origin, famed artist.
Grading Points: 5-10, Weighting Factor: 5%
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Flaws - Cracks, Brownouts, % of extinction or areas of no reflection.
Grading Points: 0-15, Weighting Factor: 15%
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Gem Grade 'D' = 0-8.3 points
Gem Grade 'DD' = 8.4-16.6 points
Gem Grade 'DDD' = 16.7-24.9 points
Gem Grade 'C' = 25-33.2 points
Gem Grade 'CC' = 33.3-41.5 points
Gem Grade 'CCC' = 41.6-49.8 points
Gem Grade 'B' = 49.9-58.1 points
Gem Grade 'BB' = 58.2-66.4 points
Gem Grade 'BBB' = 66.5-74.7 points
Gem Grade 'A' = 74.8-83 points
Gem Grade 'AA' = 83.1-91.3 points
Gem Grade 'AAA' = 91.4-100 points
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Related Gemstone Grading Reference Material
Opal Quality Factors from Gemological Institute of America (GIA).
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