Another way for pearls to be produced is when a certain stimuli, like let's say a parasite, is lodged in between the shell of the mollusk or the oyster. Then the nacre is also released around the intruder. This then leads to the build-up which produces pearls.

When you say natural pearl, these are the pearls that have been produced in nature. Cultured pearls are the total opposite wherein human beings have a role to play in producing these. Inserting foreign objects into the tissue of the mollusk or the oyster, pearl farmers can trigger the process o making pearls.

Over the years, peals have been in demand in the market, especially in the jewelry market. Pearl is symbolic to modesty and virtue. It is also a precious stone. Though they are technically organic gems, because they came from shellfish or mollusks, history of pearls as jewelry goes way back 4000 years.

How they are acquired and their appearance has changed at the turn of each century but pearl remains to be staples when talking about jewelry.

The basis for the pearl to be really precious is the time the oyster coats the sphere with nacre. Since it is rare for any pearl to have the perfect spherical shape, the rounder the better is the rule for pearl farmers.

Nowadays, pearls that are sold as jewelry today are cultured pearls. Human beings had to play a role in the creation of these jewelry in order to manifest a perfect circle pearl.

Cultured pearls can be rated on five qualities:

1. Luster and orient

Luster is the sharpness of the pearl as well as the intensity of the reflections on its surface whereas orient is those iridescent colors that a person sees when looking within the pearl. The pearl is valuable depending on the luster and orient. The higher the better.

2. Color

Usually pearls are white, black and yellow. The undertones are normally rose, pink or ever green. For personal preference, the pearls can be dyed.

3. Cleanliness

Imperfections are still evident in cultured pearls regardless of the way they were made. Real pearls, be it natural or cultivated, are to be expected on real pearls. But the rule here is the less noticeable these flaws are, then the better.

4. Shape

Spherical pearls, because of its rarity, are the most precious types of pearls. There are still imperfections even if it is round. When one looks closely, the symmetry can also be imperfect. That is exactly why there are teardrop shaped earrings made from pearls.

5. Size

Cultured pearls are often sold by diameter. They are measured in millimeters. The larger the cultured pearls, then the rarer, thus the more expensive. Therefore, the bigger the pearl, the better the price.

If you would be wearing pearls, then you should choose a set that go with one another. Let's say that you plan on wearing necklace and earrings. Then go for the pearls that have similar size, color, luster and most importantly shape. You have to match pearls because just like any jewelry, they are also an investment.

Cultured pearls are also sensitive so you have to be really careful in handling them once you bought a set. They can be scratched by other jewelry that comes in contact. Try to keep these pearls separate from one another or also from the other gems in your jewelry box.

Be it natural or cultured, once you own pearls, they are precious stones like diamonds, rubies, sapphires and the lake. Pearls have often been deemed as classy and elegant. They can match anything you wear. Take for example Marcia Cross as Bree Van De Kamp in ?Desperate Housewives? or Marge Simpson in ?The Sampsons?. They both wear pearls. They may be TV characters but they sure look classy in them. What more if a person wears pearls in real life?