When some type of irritant gets in to shell of a mollusk, layers of nacre are formed which leads to the formation of pearls. In natural pearls, the irritant may be another organism from the water. In cultured / farmed pearls, a mother-of-pearl bead or a piece of tissue is inserted (by man) into the mollusk to start the process.
Types of Pearls
Pearls are found both in freshwater and in saltwater. There are also different types of mollusks that produce very different looking pearls.
Freshwater Pearls—these pearls are grown in freshwater lakes, rivers, and ponds. Many are white and have size from 2mm to 12mm, they can also be produced in various shapes and in an array of pastel colors.
Saltwater Pearls— these include the akoya cultured pearls grown in Japanese and Chinese waters. They range in size from 2mm (tiny) to 10mm (rare) and are usually white or cream in color and round in shape.
South Sea Pearls - Australia, Indonesia, and the Philippines produce the South Sea pearl – the largest of all the pearls. They range in size from 9mm to 20mm and can be naturally white, cream, or golden in color.
Tahitian pearls are interestingly not exclusively from Tahiti – they’re grown in several of the islands of French Polynesia, including Tahiti.Their typical sizes range from 8mm to 16mm. These naturally colored pearls are collectively called black pearls, but their colors include gray, blue, green, and purple.
Pearl Quality / Grading
Pearl Gradingtakes into account shape, lustre, surface quality, nacre thickness and matching on the necklace strand. Pearls have their own jargon but most reputable pearl sellers use the A, AA, AAA grading system and follow accepted industry conventions. This system grades pearls on a scale from AAA to A, with AAA being the highest grade. This grading scale is common to freshwater and akoya pearls only, but is accepted by many with South Sea and Tahitian pearls as well. The pearl grades mentioned for our products are based on the following attributes:
AAA:The highest-quality pearl, virtually flawless. The surface has a very high luster, and close to 99% of the surface is free from any type of blemish. The necklace strand for AAA pearls will have pearls perfectly uniform in shape and size.
AA: The surface has a high luster, and close to 95% of the surface is free from any type of blemish. The necklace strand may have one or two pearls not perfectly matching with other pearls in shape or size (up to an extent of 3%-5% only)
A: This is the lowest jewelry-grade pearl, with a lower luster and/or more than 15% of the surface showing blemishes.
Pearls are measured in millimeters, across their diameter. As a general guideline, fresh water pearls from 2mm to 5mm are small sized, pearls from 6 mm to 7 mm are considered medium sized and is most commonly used size, pearls from 8 mm to 10 mm are considered large sized and pearls from 11 mm to 12 mm are considered very large and are very rare. However 10 and 11 mm pearls are very sought after pearls for people who love to wear just single line necklace without any additional embellishments like pendant or other beads/rings. Larger pearls are costlier than smaller ones but very small and very large sized pearls are most expensive pearls.
Pearls are natural products, so they are not mostly found in perfect geometrical shapes. However some do take perfectly geometrical shapes like round, oval etc. and they are sorted from whole bunch of pearls to create bunch of pearls that match in shape and size and thus a AAA necklace strand consists of pearls which are sorted to match in terms of shape and size.
Pearls come in eight basic shapes: round, semi-round, button, drop, pear, oval, baroque, and circled. Perfectly round pearls are the rarest and most valuable shape.Baroque pearls have a different appeal; they are often highly irregular with unique and interesting shapes. They are also commonly seen in necklaces. Circled pearls are characterized by concentric ridges, or rings, around the body of the pearl.
Pearls come in a variety of colours from white to black and every shade in between. All pearls display body-colour but not all pearls will display overtones or orient. It is important to distinguish between colour and overtone. For example, some naturally occurring colours are white, champagne, aqua, green, golden and black. Within each colour category there are a number of common overtones or subtle variations in the surface iridescence. Overtones are translucent colours which sometimes appear over top of a pearl's main body-colour. These overtones tend to alter the body-colour somewhat as well as adding depth and glow. For example, a pearl may be white with rose overtones.
Some pearls have no overtones at all while some display an orient that shows a rainbow iridescence which is an incredibly rare factor only seen in approximately .01% of pearls produced today. The term orient refers to the shimmering, iridescent colours which appear to move and glitter when the pearl is turned. This phenomenon is caused by the way in which light is reflected through the various thin layers of nacre which make up the pearl.
When cared for properly, pearls can last a lifetime. The best way to care for pearls is to wear them often as the body's natural oils keep pearls lustrous. However, it's important to keep them away from household chemicals including perfume, makeup and hairspray. Chemicals found in these common products can dull the luster of your pearls. It is recommended that you put your pearls on last when getting ready and make them the first thing you take off when you come home. Before putting your pearls away, wipe them with a soft cloth and store them separate from other jewelry to avoid scratching their tender surfaces.