South Sea Pearls, Broome, Western Australia (PP021)

South Sea Pearls, Broome, Western Australia by Richard Smyth

A South Sea pearl is pearl produced by the Pinctada maxima mollusk. They are currently cultured in areas throughout the Indian and Pacific Oceans, primarily in Australia, the Philippines, Indonesia and Myanmar. They are among the largest commercially harvested cultured pearls in the world. The average size of a South Sea pearl is 13 mm, with most harvests producing a range of sizes from 9 mm to 20 mm.

The South Seas lie between the northern coast of Australia and the southern coast of China. These waters are the native habitat of a large oyster known as Pinctada maxima. This oyster grows up to 12 inches in diameter, and can be nucleated with a much larger bead than other saltwater pearl oysters such as the akoya.

South Sea Pearls Come From Two Varieties Of Pearl-Producing Mollusks
There are two varieties of Pinctada maxima, the silver-lip and the gold-lip. The two are distinguished by their distinct coloration of the outer edge of the interior shell. This type of shell is also known as mother-of-pearl, and is responsible for the coloration of the cultured pearls produced, therefore the name.

There are four reasons South Sea pearls can grow to such large sizes, dwarfing many of their other saltwater pearl counterparts. These reasons are: the large size of the Pinctada maxima, the size of the implanted bead, the length of time the pearl is left to grow in the oyster, and the oyster’s environment.

What Makes South Sea Pearls So Unique?
South Sea pearls have several distinct characteristics that are unique to this gem. The nacre is unusually thick, ranging from 2 to 6 mm, compared to the 0.35 to 0.7 mm of an average akoya pearl.

South Sea pearls have a soft, satiny luster that comes from large aragonite platelets and rapidly deposited nacre due to the warm waters of the South Seas. South Sea pearls also have a subtle array of colors; typically white, silver, and golden – colors that are rare in other pearl types.

Source: https://www.pearl-guide.com/forum/content.php?60-South-Sea-Pearls