Japanese Akoya Pearl Grading

Why Mastoloni Pearls is the standard for Japanese Akoya Pearl Grading

Over the past eight decades, MASTOLONI PEARLS has built a reputation for honesty, integrity and value. Our association with pearl excellence goes back to the earliest days when we committed to maintaining the strictest quality standards of cultured pearl sorting and grading.

A large part of maintaining these high standards is educating Mastoloni’s ever-expanding network of authorized retailers in the nuances and nomenclatures of the cultured pearl industry. Due to our tireless commitment to pearl excellence, product education and ability to deliver products of an extremely high quality on a consistent basis, the MASTOLONI name is considered one of the most trusted in the world's jewelery industry.

MASTOLONI PEARL'S Sorting & Grading Standards, listed in order of importance.*

Lustre & Orient: mirror like reflective property & degree of radiant glow of surface brilliance.
Nacre (pearl skin): thickness (minimum of 0.5mm) and density (higher density is better)
Color: degree of hue from Silver/White (good) to Rose (best).
Shape: all round pearls make for a perfect necklace.
Matching: excellent matching will give the entire strand that look of perfection.
Spotting: some blemishes are always present in all pearls, it is part of the natural pearl creation process, however less spots means a better pearl.

Most pearls made available to the world markets DO NOT meet the minimum qualifications for Mastoloni's Japanese Akoya Graded Cultured Pearl Program. Depending on many factors (ie. weather & pollution levels) only 10 to 15% of the entire pearl crop may qualify for these high standards. At a minimum all pearl necklaces must be silver/white-rose color with 90-100% matching, 95-100% perfectly round, 90-100% free of "naked eye" surface blemishes, nacre thickness of at least 0.6mm, and moderate level of nacre density and good luster.

Less than 0.25% of Harvest
Perfectly deep mirror reflection with strong orient
Very thick coating (1+mm) w/ very high density
Perfect Rose Hue
Perfectly Round pearls
Exceptional Matching
No Visible Surface Spotting
Note: Availability by special order only. Japanese akoya pearl harvest has only one harvest per year; estimated wait time to find and assemble a AAA necklace is 3 to 5 harvests.

Akoya AA

Top 1-2% of Harvest
Deep Mirror Like Reflection
Very thick coating (1+mm) w/ very high density
Excellent Rose Hue
All Round
Excellent Matching
No Visible Surface Spotting

Akoya A+

Top 2-5% of Harvest
Superb clear reflection
Thick coating (.9mm) w/ high density
Good Rose Hue
All round pearls
Excellent matching
Very, Very Slight Surface Spotting

Akoya A

Top 5-10% of Harvest
Very Good Clear Reflection
Thick Coating (.8mm) w/ High Density
Good Rose & Silver/White Hue
All Round
Good Matching
Very Slight Spotting

Akoya A1

Top 10-13% of Harvest
Good reflection
Good Coating (+/-.7mm) w/ Moderate Density
All Round pearls
Good Matching
Slight Spotting

Akoya A2

Top 13-15% of Harvest
Good reflection
Good Coating (+/-.7mm) w/ Moderate Density
All Round pearls
Good Matching
Slight Spotting

Important: For more information about how we select pearls and what seperates Mastoloni's Japanese Akoya Pearl Grades from the rest of the market, please read our Detailed Nacre & Lustre Article

Necklace Sizes, Lengths (stringing) and Packaging:
Mastoloni offers its Graded Akoya Necklace Program in the following sizes and lengths:

• 5.5-6.0MM, 6.0-6.5MM, 6.5-7.0MM, 7.0-7.5MM, 7.5-8.0MM, 8.0-8.5MM, 8.5-9.0MM, 9.0-9.5MM
• 7” Bracelet, 16” Choker, 18” Princess, 20” & 24” Matinees, 30” & 34” Operas, 52” & 70” Ropes

All necklaces are double strung and knotted using white silk thread and with our official Signature clasp made of 18kt yellow or white gold and Mastoloni Pearls Certificate of Authenticity.

* These were developed to equal those of Kokichi Mikimoto and the Mikimoto company. Though fine tuned over the years, Kokichi's sorting and grading processes are still the gold standard in the jewelry industry today.

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