Most gems come from the bowels of the Earth, made by pressure and heat over millions of years. But pearls — the most famous biological gems — come from the bowels of mollusks.
While all mollusks, including oysters, mussels, and clams can technically make pearls, only some saltwater clams and freshwater mussels are used to commercially grow cultured gem-grade pearls. Mollusks make pearls as a protection against irritants that sneak into their soft tissue. They do so by exuding layer upon layer of shell material. For some animals, this material is nacre, or mother of pearl.
Nacre is a type of rind that gives pearls their pearly sheen. This brick-and-mortar process dates to at least million years in the fossil record, but natural pearls are incredibly rare. So, people today farm pearls to make more for the gem market. Since the farming process is so effective, cultured pearls are more widely available than their natural counterparts. The resulting core is, therefore, much larger than in a natural pearl. Yet, as long as there are enough layers of nacre the secreted fluid covering the irritant to result in a beautiful, gem-quality pearl, the size of the nucleus is of no consequence to beauty or durability.
Pearls can come from either salt or freshwater sources. Typically, saltwater pearls tend to be higher quality, although there are several types of freshwater pearls that are considered high in quality as well. Freshwater pearls tend to be very irregular in shape, with a puffed rice appearance the most prevalent.
Nevertheless, it is each individual pearls merits that determines value more than the source of the pearl. Regardless of the method used to acquire a pearl, the process usually takes several years.
Mussels must reach a mature age, which can take up to 3 years, and then be implanted or naturally receive an irritant. A similar process occurs when a mollusc makes a pearl. We have a similar immune response in the human body, called a granuloma.
If this happens then the granuloma may need to be removed through surgery or chemical treatment. Sometimes a human granuloma will harden through calcification. This will cause the bundle of white blood cells to harden and turn white. Tel: Email: info centreofthecell. Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website.
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