Cultured pearls are typically divided into 4 types:
- Freshwater Pearls
- South Sea Pearls
- Tahitian Pearls
- Akoya Pearls
After one has shopped around for some pearl jewellery, one would realise that freshwater pearls are typically sold for much less than their other counterparts.
Environment:
Freshwater pearls are cultured and farmed in freshwater, lakes and rivers, typically in China. Because freshwater pearls are farmed in an environment which is fairly predictable (i.e.:) lakes or manmade pools of water, supply is fairly predictable.
South Sea, Tahitian and Akoya Pearls on the other hand, are cultured and farmed in the open oceans, and are more often than not, exposed to unpredictability in weather and water conditions (e.g.: red tide) which are beyond the control of the farmers.
Oyster or Mussel?
Freshwater pearls are grown in mussels.
Photo Credit: http://cnre.vt.edu/magazine/articles/201208/cover-back/college-continues-collaborative-research.html
On the other hand, South Sea, Akoya and Tahitian Pearls are grown in oysters:
Photo Credit: http://www.patrickvoillot.com/shop/perlesdirect_en/
Quantity:
The average freshwater mussel can produce up to 32 freshwater pearls per culturing cycle making freshwater pearls easily available and in abundance. See first photo above.
On the other hand, each oyster can usually only produce 1 pearl at any one time. While theoretically each oyster can be implanted with a new nucleus up to 4 times before it is discarded, most oysters can only be cultured up to twice. Thereafter, the oyster can not be used to produce any more pearls of good quality.
Taking into consideration all above factors, it is no wonder that freshwater pearls come at a fraction of the price to South Sea, Akoya or Tahitian Pearls.
While this does not mean that one type of pearl is better than the other, consumers should be aware that freshwater pearls come at a much lower price point and should not be tricked into believing that freshwater pearls are in the same price range as ocean-cultured pearls.
There are retail jewellers and internet retailers who do not disclose the origin of their pearls and do not inform or misinform consumers about whether the pearls are freshwater pearls or ocean-cultured pearls.
What’s worse is when a jeweller tries to pass off a freshwater pearl as an ocean-cultured pearl (be it either South Sea, Akoya or Tahitian).
Below, GIA explains why freshwater pearls are less expensive than other types of pearls
https://www.gia.edu/gia-faq-freshwater-pearls-less-expensive