Pearls are nature's most unique gemstones. They come about because of a defensive process. When an intruder (typically a parasite) enters an oyster or other mollusc's shell, the oyster begins to cover it with a substance called nacre. There are many pearls in the world, and they go by many different names. Knowing the difference between different types of pearls and understanding their valuation lets buyers make the right choices and know if they are paying the right price when choosing pearl jewellery.
Natural vs. Cultivated
A natural pearl is a rare phenomenon. Only about 20 per cent of the nearly 8,000 species of molluscs in the world can consistently produce pearls. Most never do, and because parasites are shaped irregularly, most natural pearls are irregular, making round natural pearls even rarer. As such, buyers can expect prices to begin high for a single strand.
Due to their extreme rarity and high price, for all practical purposes, a buyer is unlikely to encounter natural pearls on the jewellery market outside an auction house. Cultured pearls offer variety and the authentic lustre of real nacre at a small fraction of the price.
Saltwater vs. Freshwater Pearls
The major distinction when it comes to pearls is whether they form in saltwater or freshwater. In saltwater pearl cultivation, a technician introduces an object into the mollusc, which then kick starts the process. There are three common types of saltwater pearls, produced by three different types of molluscs: the Akoya pearl, farmed primarily in Japan and China; the Tahitian pearl, found only in and around the area of Tahiti and French Polynesia; and the South Sea pearl, farmed throughout the Indian and South Pacific oceans.
Priced for their superior quality, designers fashion saltwater pearls into fine jewellery that often forms parts of investment and heirloom collections. After natural pearls, saltwater pearls are the next highest in price.
Freshwater pearls come from molluscs that live in lakes and rivers. China has been harvesting freshwater pearls since the 13th century. The nation is the world's leader in freshwater pearl cultivation as of 2014. New technology developed over the last couple of decades has meant a largely increased supply of freshwater pearls as well as great improvements in lustre, colour options, and overall quality.
Most freshwater pearls form by a slightly different process than saltwater pearls. Rather than introducing a foreign object into the shell, technicians create a small incision in the mantle of a freshwater mollusc and then insert mantle tissue from a donor mussel. The freshwater pearl is therefore made of solid nacre and is more durable than the saltwater variety.
Freshwater pearls tend to come in many shapes and are not typically as round as saltwater pearls. Freshwater cultivation also does not produce the same lustre or shine as that found in saltwater pearls. For these reasons, they price well below the level of the various types of saltwater pearls. However, jewellery designers and fashion followers prize freshwater pearls for their variety in shape and the rainbow of colours they offer, from traditional whites and pinks to vivid hues of blue, purple, and red.
There are various types of specialty pearls. Keshi pearls form by accident when a mollusc rejects and spits out the pearl before the process is complete. This results in oddly shaped pearls made of solid nacre. Mabe pearls are a form of blister pearl that forms against the side of the shell rather than independently. A mabe pearl is a perfectly semi-round blister pearl.
How to Buy Pearl Jewellery on eBay
On eBay, an educated buyer can find reputable sellers offering a range of pearls both as loose stones and as fashion and fine jewellery. Choosing pearls means first deciding on a price range as well as what you anticipate in terms of how you use or wear them. Simply type your query into the search bar atop any eBay page. Knowing whether you are looking for a piece of fine jewellery or a trendy fashion item, or what type of pearl you want, means you can narrow your search terms to find the results you want.