Chinese Jade of Five Centuries

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Joan M. Hartman. Chinese Jade of Five Centuries

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Chinese Jade of Five Centuries

Chinese Jade

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The expert can usually determine whether a carving is nephrite or jadeite or neither. He is aware of color, polish, and mineral composition. But even the experienced are fooled occasionally. There are many stones which imitate jade. Why care if the carving is jade or not as long as it looks as good? Why is a carving more valuable because it is jade rather than serpentine (sometimes called onion jade or new jade), soapstone, green quartz, green garnet, chrysophrase, smithsonite, or chalcedony? The answer is a multiple one. First of all, fine jade rough is available in very limited quantities. Secondly, other minerals which bear a strong resemblance to jade generally do not exhibit the beautiful color properties of nephrite and jadeite. Last but not least, jade is more durable than its imitators. As usual, there is no satisfactory substitute for the real thing.

Minerologists have devised various tests to establish whether or not a particular example is genuine jade. The simplest method is to attempt to scratch the surface of the stone with a sharp blade. Theoretically, if it scratches it is not real jade. However, certain quartzes and types of serpentine are virtually as hard as jade and will not yield to the knife blade or razor edge. Hence the scratch test is not conclusive. Recently, further difficulty has arisen with the advent of stainless steel razor blades. These harder instruments will bite into genuine jade material, so this test is indecisive.

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