Pearls have been a valued in history for longer than any other gem. Pearls are a very unique and interesting gem. They are the only gemstone grown inside of a living organism. Pearls are formed in oysters or mollusks when a foreign substance, generally a parasite, enters inside the shell and reaches the soft mantle tissue. The mantle’s epithelial cells form what is known as the pearl sac in response to the irritation. The pearl sac secretes a crystalline substance called nacre, which is the same substance that makes up the interior of the shell, eventually, it builds up layers surrounding the irritant and therefore forms the pearl. Natural pearls are rare, and are normally irregular in shape, keeping the shape of the original irritant. Finding a round natural pearl is very rare.
Pearls began being produced artificially in the early 20th century by Japanese researchers. This method involves placing a foreign substance or nucleus into the tissues of the oyster or mollusk, and returning it back into the ocean. These pearls are developed naturally after placing the substance into the oyster or mollusk, but they are given the name cultured pearls. Kokichi Mikimoto was credited for perfecting a technique to artificially develop round pearls in akoya mollusks, getting a patent for this process in 1916. Since then this technique has been altered and improved and is now used on freshwater, Tahitian, and South Sea pearls. Finding natural pearls today is rare, although they are still available they are very expensive, and a cultured pearl is a great alternative with equal quality.
Origin
Pearls originate from oysters and mollusks.
Properties, Treatments & Lab Created
Pearls are rated a 2.5 – 4.5 on the Mohs scale. They scratch easily and must be worn and stored with care.
Pearls are sometimes dyed to change the color of them.
There is no lab form of a pearl. Cultured pearls are an alternative to natural, but are still grown in a similar environment and in the same way they would occur in nature except the parasite is placed in the host instead of it occurring naturally.
There are also simulants available, these are not grown naturally in any way and can even be made from plastic.