In his book "Pearls", Fred Ward states,
" A great irony of pearl history is that the
least expensive cultured pearl product in the market today
rivals the quality of the most expensive natural pearls
ever found."
The Chinese first cultured shell mabes but true freshwater pearls were first cultured by the Japanese at lake Biwa.
These freshwater pearls were uniquely colored and showed extremely fine luster.
But huge land mass with large lakes and rivers coupled
with cheap labor are on the side of the Chinese. The newest
pearls coming out of China rival Japanese saltwater pearls
at a fraction of the price
Add to that the new colors and the production of all-nacre
pearls, the Chinese may soon control the pearl industry.
Cultured freshwater pearls are produced by a slightly
different system than saltwater pearls.
Technicians open the shells slightly then cut tiny slits
into the mantle tissue inside both shells, then insert
a small piece of live mantle tissue from another mussel
inside the slits.
That alone is enough to initiate nacre production. So
most cultured freshwater pearls are all nacre, just as natural
pearls are.