Saturday, October 18, 2008

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Before You Buy Colored Gemstones

By Carly Wickell, About.com

What could be more tempting than a jewelry display packed with a rainbow of brightly colored gemstones? Go shopping and you'll see natural, synthetic, and imitation stones of every color, shape, and size. Can you tell one type of gemstone from another? Here are some tips to help you understand the differences so you can ask the right questions before you buy a colored gemstone.

Natural Colored Gemstones

Natural stones are courtesy of nature, with no interference from humans. Don't assume that just because it's natural a stone should carry a high price tag. Prices are driven by desirability, quality, and availability. A brilliantly colored ruby with "perfect" clarity will cost thousands of dollars more than a garnet of similar quality. Become acquainted with the gemstone market before you buy.

Gemstone Treatments

Most natural stones are treated to improve appearance. Heat and radiation change or enhance colors. Diffusion deepens color, but only within a stone's outer layers. Oil and waxes are used to fill-in surface-breaking fractures. Some treatments are permanent--others are not. Treated gems can be a good choice when you know what you are buying and pay a price that reflects a stone's true quality.

Synthetic Colored Gemstones

A synthetic stone shares a natural stone's physical, chemical, and optical qualities. The difference? Synthetics are created in a lab. They've been around for a long time, but modern technology allows us to grow stones that are difficult to distinguish from their natural counterparts. Ask for a lab certificate to verify authenticity before paying top dollar for a stone represented as natural.

Imitation Stones

Imitation, or simulated, stones may at first look like the real thing, but that's where the similarities end. They do not share physical characteristics with natural or synthetic stones. Many are made of glass or plastic and most can be detected easily by a jeweler. Moissanite is a newer diamond substitute that's even fooling the pros.

Composite Stones

Doublets are stones that are assembled using a larger chunk of an inexpensive stone (or glass) which is topped by a thin slice of the genuine stone. The division usually isn't obvious without magnification. One type of doublet sandwiches a colored bonding agent between two clear stones to mimic a colored gemstone. Triplets are composites assembled in three parts.

Bottom Line

Imitation and synthetic stones make lovely jewelry--there's no reason to avoid them. What you do want to avoid is paying too much for a misrepresented stone. Read as many resources as possible and start looking more closely at jewelry. Ask questions when you shop. It won't make you an overnight pro, but in time it will help you become a more savvy consumer.

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