The fascinating world of natural and cultured pearls

In the lustrous world of authentic pearls, there are two distinct and distinctive types of pearls that are often compared to one another: natural pearls vs cultured pearls. Both types are genuine pearls. However, the way they are formed and the stark difference in their price that makes them distinctly different.

A natural pearl is formed organically when an irritant such as seawater sand or dust, accidentally finds itself inside the oyster’s soft tissue muscle. This irritant activates the oyster’s defence mechanism, causing it to produce layers of secretions. The secretion (also called nacre) slowly develops into a natural pearl in the oceans and rivers of the world. Natural pearls are rarer and therefore more valuable. 

It can take more than 100,000 oysters, the deep-sea-living creatures, to make just one strand of pearls. And, with so many sea-borne predators, ocean-pollution, oyster divers and other factors that cause premature deaths for the animals, finding quality gems when diving for pearls is quite rare these days. Natural pearls are harvested through deep sea pearl diving, an undertaking fraught with dangers and uncertainties to the diver.

A cultured pearl is a genuine pearl, produced by an oyster or mollusc, but with human assistance. There are two main types of cultured pearls: freshwater and saltwater pearls. Interestingly, a cultured pearl is created in pearl farms through the very same process. However, with a BIG difference—the irritant is not inserted accidentally but rather, purposefully introduced into the oyster. Thus, while cultured pearls are regarded as genuine, they are created with human assistance. 

Once the irritant is placed inside the oyster, the rest of the cultured pearl growth process is natural. The animal is tended to and nurtured by pearl farmers who, like agricultural farmers, want nothing more than a bountiful harvest. With luck, experience and expertise, the oysters go on to create high-quality gems, with the same pearl quality as natural pearls. Incidentally, the pearl is the only gem created by a living animal and the only gem in the world that does not need to be cut, polished or mined.

Kokichi Mikimoto, a Japanese entrepreneur, was the first to create a cultured pearl. For over two decades, he explored and tested various methods of cultured pearls in his oyster beds. He received his patent for cultured pearls in 1896.   

Because cultured pearls are created in controlled environments, the survival rates of the oysters are much higher. This allows pearl farmers to produce high-quality, authentic pearls at higher rates than what can be obtained by oyster divers. According to the American Gem Society, most of the ocean’s natural pearls have already been harvested by pearl divers.

Just like natural pearls, cultured pearls are created in both freshwater and saltwater. Different types of oysters are used to cultivate different saltwater and freshwater gems in various types, colours, lustres sizes, shapes, shades, grades and values.

Major types of cultured whole pearls:

Akoya Cultured Pearls

Akoya cultured pearls are the most familiar type of saltwater cultured pearl to most people in the U.S and other western markets. Many customers think of white or cream colored akoyas as the classic pearl used for jewellery, especially single-strand necklaces. Japan and China both produce Akoya cultured pearls.

South Sea Cultured Pearls

The leading sources of these saltwater cultured pearls are Australia, Indonesia, and the Philippines. The South Sea cultured pearls can be white to silver or golden, depending on the type of oyster. Their large size and thick nacre, due to a long growth period, and their limited critical growing conditions are all factors contributing to their value.

Tahitian Cultured Pearls

Cultivated primarily around the islands of French Polynesia (the most familiar of these is Tahiti). These saltwater cultured pearls, also known as black pearls, range in colour from gray, black or brown, and they can have blue, green, purple or pink overtones.

Freshwater Cultured Pearls

Freshwater cultured pearls are the most commonly produced pearls and they are one of the most popular pearl types among shoppers and jewellery designers. This is due to their remarkable range of sizes, shapes and colours, plus their commercial availability at lower price points. They are usually cultured in freshwater lakes and ponds, often with many pearls grown in one oyster.

Fresh water pearls are usually found in the lakes and rivers in China. In recent years, modern technology has value added to the quality of fresh waterpearls  that are cleaner, rounder and more lustrous.  Since they can be mass produced, freshwater pearls are available at astonishingly affordable prices. The typical size of a freshwater pearl ranges between 5mm to 10 mm, although they can also go up to 13 mm. China is the leading source of freshwater cultured pearls.