Pearls have been regarded as one of the most valuable gem materials. They have been used for adornment for
6,000 years. This gem, a gift of the sea, has a myth and lore dating back to the beginning of time. A Hebrew
legend says that pearls were the tears of Eve after being banished from the Garden of Eden. In America, it has
been a long held tradition that a bride receives a strand of pearls as a bride's gift to wear on her wedding day.
Some Characteristics of Pearls
Pearls are produced by molluscs, rarely by snails. They consist of mother-of-pearl, which is mainly calcium
carbonite (in the form of aragonite), and an organic horn substance (conchiolin) which are formed concentrically
around microcrystals. They have a hardness of 3-4 on the Mohs scale.
Types of Pearls
Cultured pearls are not imitation but a natural product which has been produced with man's help.
Today, cultured pearls amount to over 90% of the total pearl trade. Cultured pearls produce the
finest pearls on the market today. Pearls are an organic gem material that grows in an oyster.
When a piece of the mantle or beard of an oyster of an oyster is implanted into the heart of his mollusc,
the material that forms around it is called nacre. Pearls are made up of layer upon layer of nacre.
The longer these oysters are left in the water, the larger the pearl grows, until it reaches capacity
for that particular type of oyster. Specific types of are used to grow specific types of pearls.
Cultured Akoya Oyster
The Akoya oyster produces pearls from 2.0 mm – 10.0 mm, usually spherical in shape. The usual color is white or
cream in color, but pink and a deep rose pink are also achieved. Akoya pearls are usually bleached, dyed or tinted
to improve their color. The most desirable shape is completely spherical.
Cultured South Sea
South Sea Cultured Pears are grown in the world's largest oyster. The pearls grown in this oyster
usually range from 9.0 mm – 18.0 mm or larger in size. Less than 1/3 of the productions of South Sea
pearls are round; making these pearls very rare. White, light cream and gold are the most sought after
colors of the South Sea Pearls. Silver, yellow, blue, and yellowish-orange are other colors available.
South Sea Pearls are rarely dyed to improve their colors.
Cultured Tahitian Pearls
Tahitian cultured pearls are grown in the warm waters of French Polynesia. A particular oyster, the
black-lipped oyster, is responsible for the exquisite size and color of Tahitian pearls. These pearls
grow from 8.0 – 14.0 mm or larger with less than half of the pearls being spherical in shape. The most
common shapes that are symmetrical but not round are oval and drops. Non-symmetrical baroque and semi-baroque
shapes are also common. Tahitian pearls come in a glorious array of colors. These include black, gray, brown,
green purple, and yellowish-green. Several colors are more highly valued. The most highly valued color is peacock
a combination of dark green-gray or blue-gray with a rose or purple overtone. Aubergine is a very desirable
grayish purple color. Yellowish-green or greenish yellow pearls are called pistachio, another excellent color
that is also highly valued. Tahitian cultured pearls are rarely dyed to improve their color.
Freshwater pearls are grown in mussels, not oysters. Their production has given us a wealth of new shapes
like biwa, coin, button, etc. and every color of the rainbow. Many of these pearls are dyed to give us these
vibrant colors. The production of freshwater pearls is very high, making the cost very affordable and
providing a fun choice in jewelry.
Tips to Care for Pearls
Proper care of pearls is very important. The porosity of pearls is what enables them to be dyed. Never put pearls
in an ultrasonic cleaner, water, soapy solutions or jewelry cleaner. Chemicals can also be absorbed into the nacre
causing discoloration. A good rule for pearls is that they are the last thing you put on after you have applied perfume
and/or hairspray and the first thing you take off.