Pearl Grading
By jiang liu

A-AAAA Pearl Grading for Akoya and Freshwater Pearls

The A-AAAA Grading Scale has been adapted from the Tahitian and South Sea pearl A-D Grading systems that most pearl farmers use to evaluate their pearls. With the A-AAAA Grading Scale, each grade has a specific range of Value Factors that a pearl has to meet in order to meet the requirements for that grade.
Value factors are weighted heavily towards Luster, Surface Quality and Nacre Thickness, with factors like Color, Size, Shape and Matching accounting for a lesser percentage of a pearl's total grade within the A-D / A-AAAA Grading System.

AAAA Grade / A Grade

  • Surface Quality is 95% Clean or better.
  • Luster is Very High to Excellent: Reflections on pearl surface should be Easily Recognizable.
  • Pearl Earrings are clean on front and sides.
  • Pearl Necklaces and Bracelets will be blemish-free for casual observers. Some tiny inclusions allowable, but nothing major.
  • Akoya pearls should feature Excellent matching for necklaces and bracelets. There should be virtually no difference between each pearl in a necklace, bracelet or matched set.
  • Freshwater pearl necklaces, bracelets and matched sets will have very little differences for matching for shape, size and surface quality.

AAAA-Grade

AAA Grade / B Grade

  • Surface Quality is 90-95% Clean or better.
  • Akoya pearls feature thick nacre measuring 0.4mm or more. Freshwater pearls are solid nacre.
  • Luster is Very Sharp to High: Reflections on pearl surface should be Very Good, mostly distinguishable with some slight blurring.
  • Earrings are clean on fronts. One to two small inclusions allowable on sides or backs.
  • Pearl Necklaces and Bracelets will be mostly blemish-free for casual observers.
  • Akoya pearls should feature Excellent to Very, Very Good matching for necklaces and bracelets. There should be little to no difference between each pearl in a necklace, bracelet or matched set.
  • Freshwater pearl necklaces, bracelets and matched sets may feature some differences in matching for shape, size and surface quality.

AAA-Grade

AAQuality / C Grade

  • Surface Quality is 75-80% Clean or better.
  • Nacre is solid for Freshwater pearls. May be thin in places for Akoya pearls.
  • Luster is Good to High: Reflections on pearl surface will be blurry.
  • Earrings are not clean on fronts.
  • Pearl Necklaces and Bracelets will feature multiple blemishes, and some deeper inclusions.
  • Akoya pearls should feature Very Good matching for necklaces and bracelets.
  • Freshwater pearl necklaces, bracelets and matched sets will feature differences in matching for shape, size and surface quality.

AA-Grade

 

A Quality / D Grade

  • Nacre is visibly thin for Akoya pearls and nucleus will be visible under certain lighting conditions. Freshwater pearls are solid nacre.
  • Luster is Fair to Good for Akoya and Freshwater pearls. You should be able to see your face's outline, but not any fine details.
  • Light sources reflected on pearl surfaces will be blurred with fuzzy edges.
  • Blemish free 60% of all pearl surfaces.
  • Pearl earrings will have marks on the front.
  • Necklaces will have blemishes easily visible to the casual observer with multiple deep inclusions visible.
  • Decent pearl matching; for Freshwater and Akoya pearls some variation in color, tone, luster, shape or size may occur.

A-Grade

A-D Tahitian and South Sea Pearl Grading

The A-D Grading Scale is primarily used by farmers and processors for Tahitian and South Sea pearls. It easily corresponds to the more widely known A-AAAA Grading Scale that Preala uses. With the A-D Grading Scale, “A” represents the highest quality, and then moves down through B,C and D which represents the lowest, commercial grade.

Let's look at these in more detail:

A Grade / AAAA Quality

  • Extremely thick nacre. For Tahitian pearls, nacre depth is a minimum of 0.8mm. White and Golden South Sea pearls average 2-4mm nacre thickness.
  • Surface Quality is 90% clean of blemishes or better.
  • Earrings, Pendants and Rings will set clean on front and sides. One small inclusion allowable on back.
  • Necklaces will present as mostly clean, with a few small, shallow blemishes allowable with up-close scrutiny. No deep inclusions allowed.
  • Luster will be Very High to Excellent. Reflections in the surfaces highly detailed, but some blurring is allowable.

A Grade

B Grade / AAA Quality

  • Extremely thick nacre. For Tahitian pearls, nacre depth is a minimum of 0.8mm. White and Golden South Sea pearls average 2-4mm nacre thickness.
  • Surface Quality is 80% clean of blemishes or better.
  • Earrings, Pendants and Rings will set clean on front. Small, shallow inclusions allowable on sides, and one or two inclusions allowable on back.
  • Necklaces will present as mostly clean, with small, shallow blemishes allowable throughout the strand. Up to 2 deep inclusions allowed.
  • Luster will be Very High. Reflections in the surfaces mostly detailed, but blurry.

B-Grade

C Grade / AA Quality

  • Extremely thick nacre. For Tahitian pearls, nacre depth is a minimum of 0.8mm. White and Golden South Sea pearls average 2-4mm nacre thickness.
  • Surface Quality is 70% clean of blemishes or better.
  • Earrings, Pendants and Rings will not set clean on front. Moderate inclusions allowable on front and sides, deeper inclusions allowable on sides and back.
  • Necklaces will present as spotted, with combination of small and medium-sized blemishes allowable throughout the strand. Up to 4-5 deep inclusions allowed.
  • Luster will be Good to High. Reflections are blurry.

C-Grade

D Grade / A Quality

  • Extremely thick nacre. For Tahitian pearls, nacre depth is a minimum of 0.8mm. White and Golden South Sea pearls average 2-4mm nacre thickness.
  • Surface Quality is 50% clean of blemishes.
  • Earrings, Pendants and Rings will not set clean on front. Moderate inclusions allowable on front and sides, deeper inclusions allowable on sides and back.
  • Necklaces will present as spotted, with combination of small and medium-sized blemishes allowable throughout the strand. Up to 8 deep inclusions allowed.
  • Luster will be Good to Poor. Reflections are very blurry.

D-Grade

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