Pearl farming takes place mainly in midwestern states of the United States, as well as the coasts of Canada down to the Gulf of Mexico. The first artificial pearl was created in 1893 by Kokichi Mikimoto. Pearl farming started growing as an industry between 1908 and 1912. Freshwater river mussels are harvested here. A second group of bivalve mollusks are saltwater pearl oysters. “Cultured pearls” is a type of pearl made by humans. This is done by inserting a tissue graft that came from a mollusk. When the pearl sac is created, the inside releases nacre made of calcium carbonate, which is otherwise known as “mother of pearl”. Colored pearls are human creations, made when different chemicals are inserted inside a shell, such as cobalt chloride which makes a pinkish color. This is done similarly with rubies and sapphires as well.
At the start of the process of harvesting pearls from oysters, larvae freely float around in controlled water environments for a few weeks. During the course of a few months, they turn into baby oysters where they spend about 1 to 2 years to fully grow as oysters. When tissue of the mantle is injured or the outer rim of a mollusk shell bivalve is damaged, a pearl can then be formed. In response to this damage, the tissue secretes mother-of-pearl, otherwise known as nacre, into a pearl sac and a cyst is formed while the damage heals. As nacre builds up through layers of aragonite tablets, it is filling the pearl sac, eventually forming a pearl. The process of artificially making pearls is slightly different from this. After getting the mantle tissue from one oyster, the second oyster is worked on. An oyster is placed into warmer water to relax it and then is gently opened and put on a stand to be operated on. The nucleus will be inserted along with a small piece of mantle gland. This oyster will be placed back into water and over the course of a few years, the nucleus is coated with many layers of nacre. When you cut a pearl in half, you can actually visibly see the layers, which I think is pretty cool. However, natural and artificial pearls’ inner structure is different which can be seen by using x-rays. This can reveal the nucleus of a pearl. There has been a recent debate over pearl farming, regarding whether or not it is cruel. Pearl farming does have its benefits, mainly financial and creating jobs for a new industry, such as making jewelry. However, there are some negative environmental impacts. Some of these impacts include water quality loss from the chemical treatment of the pearls and from hydrocarbon spills. This may introduce us to the spread of diseases from seeding and overharvesting. Although in general, if the pearl farming industry doesn’t get too greedy and use too many chemicals and overharvest, this industry doesn’t seem to have many negative impacts in the environment. Harvesting pearls from oysters actually doesn’t kill it, and it isn’t harmed in the process either |