Do pearls come from clams? Where these organic gemstones can be found.
Mythili Devarakonda | USA TODAY
"Nature has a lot to offer to humans. Most precious jewelry is made from metals and stones buried deep within the Earth’s surface but the discovery of these rare jewels is not just limited to land. The Earth’s surface is also three-quarters water, and valuable gemstones like corals and pearls are produced in the vast sea.
Historically, pearls were considered a symbol of wealth and riches until the start of the 20th century when the world’s first cultured pearl came about. Until then, deep sea divers had to risk their lives to find and retrieve pearl oysters. But where exactly do these pearls come from? And how are they formed in nature?
Only oysters make pearls All bivalve mollusks (including clams, mussels, and scallops as well as oysters) are capable of producing pearls, however only certain mollusk groups create nacre, the substance that gives gem pearls their characteristic luster.
All bivalve mollusks (including clams, mussels, and scallops as well as oysters) are capable of producing pearls, however only certain mollusk groups create nacre, the … Show more
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Where do pearls come from?
Pearls are produced by marine and freshwater mollusks known as bivalves. Bivalve mollusks include oysters, mussels, clams, scallops and more.
In 1908, American gemologist George Frederick Kunz co-wrote “The Book of the Pearl,” in which he shared the belief that a fish-eating tribe along the coasts of India might’ve discovered pearls while opening oysters in search of food.
Scientifically, pearls are formed by marine oysters and freshwater mussels as a natural defense against irritants such as a parasite or grains of sand entering their shell, according to the Natural History Museum.
To protect their fragile bodies, these bivalves secrete layers of aragonite and conchiolin, the same substances that make up their shell. Together, these secretions form a material called nacre.
Nacre, also known as mother-of-pearl, then forms a layer around the irritant to protect the mollusk. Nacre gives the pearl its luster and gem-like sheen. While all mollusks can technically make pearls, only some groups make them of nacre.
With commercially cultured pearls, an external irritant is manually inserted in the mollusk to produce nacre and subsequently, the pearl. Farmed or cultured pearls are generally less expensive than naturally-occurring pearls which are extremely rare.
How long does it take for pearls to form? ... "
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