Finding a Good Buy
But to spot good pearls, you need to know how to judge their quality. So look at pearls whenever possible. Take time to analyze them. Ask jewelers to explain their quality differences. Gradually, you'll learn to recognize good value, and you'll see that the pearl is a remarkable gem which has no peer.

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Pearl treatment
All pearls must be cleaned and washed to remove residue and odors. They are typically tumbled in rotating barrels with salt during this procedure. The tumbling must be closely monitored; otherwise some of the nacre may wear off. There are other processes which are not considered routine and which should therefore be disclosed. Some of these are listed below.

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South Sea Pearls
South Sea pearls are priced according to their luster, color, shape, surface perfection, size and nacre thickness. But low price does not necessarily mean low quality when it comes to shape, color and size. The low price results from a greater supply and a lower demand of certain colors, shapes and sizes. Luster, nacre thickness and surface perfection, on the other hand, do affect the actual quality of pearls.

Pearl Price Factors
Luster,Surfacre,Shape,Color,Size,Nacre thickness and quality,Treatment status,Pearl type

Black Pearls
Some people use the term "black pearl" to refer to any dark colored pearl, dyed or natural color. Black pearls are not necessarily black. More often than not they range from a light to very dark gray, but they may also look green, pink, lavender, blue or brown. It's the oyster source, not color, that determines if pearls are called black pearls. "Black pearl" is a generic term that refers to pearls from:
• Black-lipped pearl oysters (Pinctada margaritifera), Western to Central Pacific & Indian Oceans.
• La Paz pearl oysters (Pinctada mazatlanica), Eastern Pacific between Baja California & Peru.
• Rainbow-lipped (western-winged) pearl oysters (Pteria sterna), Eastern Pacific between Baja California & Peru.

Imitation or Not?
Imagine a rosary-bead maker watching a fish being scaled in a basin of water. The water has colorful, pearly reflections which seem to form as the fish scales dissolve. The bead maker then gets the idea to filter the water, recover the pearly substance from it and mix it with a kind of varnish. Later he coats the inside surface of a hollow glass bead with the pearly mixture, fills the bead with wax, and what's the result? The birth of the modern-day imitation pearl.