Grading Mabe Pearls

VII. Grading Mabe Pearls

Mabe pearls can be graded using most of the same grading standards that we have already seen for the traditional cultured pearl:
  1. Size
  2. Shapes
  3. Color
  4. Luster
  5. Surface Quality
  6. Nacre Quality
But we can add an additional one that is quite important for this variety of pearl:

7. Dome Height

Even so, many of these value factors are not as employed as strictly as they are with regular cultured pearls, but may actually be quite lax, and if we know that there is no standardized pearl grading system, we can quite confidently say that there is an even less formal grading system for Mabe pearls.

Let us review each one of these attributes and how they pertain to Mabe cultured pearls.

1. Size
Mabe pearl sizes are highly variable. From the small 3-4 mm “Akoya Mabe” first made by Mikimoto at the start of the 20th Century all the way to large “Blister Mabe” that may reach sizes of 10 cm (almost 4 inches), but on average we can say the diameter of the “classic Mabe” is between 12 to 18 mm (0.47 and 0.70 inches).

Distributors that have a good production and inventory of Mabe pearls may have different price points for size intervals, others will not care for this attribute and will not distinguish between these.

An example of this are “Cortez Mabe”, that have three different size considerations:
Mini and Micro Mabe: Mabe pearls that have sizes between 5 and 10 mm in diameter. The smaller size does not result in a smaller value, because it is more difficult to process these smaller pieces.
Mabe: The common sizes are between 12 and 18 mm in diameter and exclude all pearls that have a “shell fringe” around the Mabe and that would be considered as a “cultured Mabe Blister”
Blister Mabe: Usually of a larger size than the traditional Mabe, usually of at least 20 mm and even up to 50 mm in diameter, and usually having a shell fringe that varies in size and shape, depending on the piece.
Mabe pearls from Sea of Cortez

Cortez Mabe Pearls

A remarkably interesting thing to notice here is that a smaller size does not necessarily mean a smaller economic value: it is much harder for the processors to manufacture smaller Mabe pearls, so they may even demand for a higher price for the smaller pieces, and this is the opposite to (loose) cultured pearls.

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