2011年11月10日 星期四

How To Invest | Identifying Cultured Pearls From Natural Pearls

Natural Pearl Jewelry is acquired mainly from estates and many Natural Pearls, singly or in necklaces remain in private hands.

Embellished with enamels, rubies, diamonds, a single sapphire, and pearls, lots of them, all natural pearls, adorns the crown of Emperor Rudolf II, that dates to circa 1602!
The Imperial Scepter of Austria made by the court goldsmith Andreas Senbruck in 1612 also echoes the decorative design of the crown and is embellished with natural pearls and a single blue sapphire.

The Thickness of the Nacre is the Key in Identifying Natural Pearls.

A simple method in identifying Natural Pearls is by checking the thickness of the nacre layers.

You can do this by rolling a strand of pearls on a white surface under a strong light. Thin skinned Pearls will wink at you. They will appear brighter and darker as the Pearl is rotated. The winking is the bead showing through the nacre. Winking Pearls will not be not Natural Pearls.

Candling is another way of identifying Natural Pearls. The Pearl is held over a concentrated light source or placed on the lens of a flashlight. A maglight is perfect for doing this test. In thick skinned Pearls the bead will appear as a dark round smudge. A series of parallel stripes will be present in thin skinned pearls. These stripes are growth layers. Pearls with these striations have very thin nacre and will therefore not be Natural Pearls.

Another simple test to help in identifying natural pearls comes to us from the pearlers themselves who dived for Pearls! I also had to dive deep to find this Natural Pearl test. The Touch test.

The old pearl divers didn't call Natural Pearls, "cold flames" for nothing. If the Pearl is a Natural Pearl it will be cool to touch. The touch test is a particularly useful test in identifying natural pearls set into an antique ring setting as here you will not be able to check the drill-hole for nacre thickness or perform the winking test that is useful for a strand of pearls. If you have a strand of Pearls you think maybe natural, it will be money well spent to have your pearls x-rayed by a gemological laboratory.

Another Natural Pearl test is called the sun test. This test involves taking the strand of Pearls out into the sunlight. Unless they are very, very expensive, genuine Natural Pearls won't be perfectly matched under the sun. You will be able to see variations in their size, shape and color. If the Pearls are perfectly matched for size, shape and color they will not be Natural Pearls.

Natural pearls are less transparent than Cultured Pearls. If you place a Natural Pearl against a dark background-like a box lined in black cloth-and put it under a strong light, the natural pearl will look like a small, white, homogeneous ball with no discernible inner rings. When you do the same to a Cultured Pearl, you will see a thin brown line between the nacre layer and the nucleus of the Pearl.

Another way to help in identifying Natural Pearls is by examining the Setting. If you see a Picasso in someone's home, you can be pretty sure it isn't the original piece of artwork. Similarly, you can gain valuable clues about a Pearl's authenticity by looking at its surroundings.

Natural pearls will have settings of gold, silver, or platinum. The setting will of course pre-date the 1920's. The setting rule is not a rule set in stone; many high quality Cultured Pearl necklaces will have high quality settings. Even so, the setting and the age of the jewelry will provide clues to help you reach a conclusion.

If still in doubt, instruments used for testing is the pearl microscope (pearlometer) but the most efficient tests are by means of the endoscope or a modern X-ray test called a SKIAGRAM or for undrilled Pearls, the lauegram.

It is important to note however, that sometimes identifying Natural Pearls from cultured Freshwater Pearls is nearly impossible. You can't tell the difference even by X-raying these Pearls. The nucleus, whether inseminated or naturally occurring will decompose and usually leave a small void inside the pearl. The tiny little void will be the only piece of evidence that remains.

by Evie Hammouda-Eyre of Antique Jewelry Investor. Antique Jewelry Investor is the first resource center on the internet dedicated to providing free information on how to invest safely in Antique Jewelry. For more info on this topic. See

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