News-Antique.com - Mar 09,2009 - Ways To Evaluate Your Vintage and Antique Jewelry
Most collectors and dealers of vintage and antique jewelry, are always looking for information on the value of their jewelry
They might be curious about the metal of a piece that looks like gold or a stone they suspect might be a natural gem.
What's your next move? There are many jewelry books that have sections on how to help you identify jewels and metals. One tip with stones is the visual, which by holding it up to good light and looking through a 10 - power loop you view the stone for what is called zoning. This is a variation in color in some area of the stone. This variation can indicate whether it is a natural gem or a pretty piece of glass. Glass will be clear and have an even color with possibly small bubbles. Another tip is, does the piece feel cool, if it does that is an indication of the real thing. Faceting of the stone is another clue to look at. A real gem does not have precise faceting as synthetic stones do.
There are other simple tests. For amber one is static electricity, rub the piece of amber and hold a piece of tissue next to it, if it draws the tissue to it then it could be amber. Another test is using a hot pin in an inconspicuous place, if it smells of like pine it could be amber. Neither of these test are definite. Gutta-perca is easy, just rub briskly on a piece of cloth, it should have the smell of burnt rubber. There are also tests for diamonds, but I use a diamond tester. They are a little expensive but worth it. Ivory is hard to identify unless you're an expert. Pearls are easy, just rub them against your teeth, if they feel scratchy they are probably the real thing, if smooth on your teeth you probably have simulated pearls. Celluloid smells like camphor if you use a hot pin, and tortoise shell smells like burning hair, with a hot pin. Synthetic stones have become so perfected it really takes an expert to determine if it is real or not. Most of us can tell the difference between plastic or glass by clinking it against the teeth. For testing gold I prefer a gold tester. Silver has been hallmarked for hundreds of years. Although you can still come across a piece that isn't signed.
With all the book references for testing stones and gold and silver some people feel confident in making determinations about their antique and vintage jewelry for pricing. And yes some old costume jewelry had real stones. Diamonds were sometimes set in sterling.
On occasion I purchase better or fine jewelry and consider its worth considerably more than I paid for it. I find I need the advice of an expert. I head out to our local jeweler who employs a gemologist that has had an education on the