Solving the Mysteries of Old Chinese Nephrite Jades

EricHoffman

EricHoffman

The April 7, 2008 chapter meeting, brought an informative lecture with PowerPoint show about the little-known gem nephrite jade.

A local expert named Eric Hoffman, who has been studying, buying, selling and writing about nephrite for over 35 years, gave the talk.

Nephrite has been highly prized in China for more than 5000 years. Whitish and yellow pebbles were discovered in the Karakash River in the Xinjiang Province. Karakash means “black jade” in Chinese. It is tougher than it’s better-known cousin, jadeite, due to a different structure.
pic1The nephrite is made of interlocking fibers with a hardness of 6-6.5, whereas jadeite has interlocking crystals with a hardness of 6.5-7. Because of this structure, nephrite can be carved very thinly.

One of the oldest known pieces of carved nephrite is a plow point dated 5000-7000 years old.
pic2During this time, it was also carved in to axes, chisels and grain cutters. The uses were more utilitarian than ornamental.

pic3

As time progressed to 3500 B.C., we began to see more three-dimensional carvings. These were done using bamboo with quartz sand imbedded.
pic4There were no metal tools yet. Moving to 1500 B.C., technology improved to the development of metal tools and much more intricate carvings began to emerge.
pic5Even though nephrite can come in natural colours other than green and white, by the time of the Ming Dynasty, colour was introduced to the carvings in the form of dyes and stain.
pic6
The challenges that one can face when buying nephrite include determining if it is, indeed, nephrite, is it old and is it Chinese? One can perform various gemological tests for the first challenge.
pic7Other possibilities would be serpentine, bowenite, glass or chalcedony. Hardness, refractive index and specific gravity should do the trick.
pic9
As for Chinese origin, the motif of the carving would be considered. Some Indian motifs have been confused for Chinese. One must study the historical aspects to be able to determine this.

The age is the most difficult to assess. Since there is no scientific way to test for this, other methods must be employed. Motif as well as how the piece was actually carved can indicate age, i.e. metal versus some other technique.
pic10One must ask several questions, such as: Is the material from the period claimed? What kind of tooling marks or drill holes does it have?

pic11

Does the piece have provenance that is documented and published. Are there other similar pieces on the market? What are the seller’s credentials? If the deal sounds too good to be true…….
pic13In conclusion, Chinese jade is a fascinating entity and there are many fakes. When in doubt, consult with a true expert!
pic14Raffle Tickets are sold at every meeting to help raise money to cover chapter costs. 50% of the money raised goes to the chapter and 50% goes to a lucky raffle ticket holder.

Bobby Mann & Eric Hoffman

Bobby Mann & Eric Hoffman

The lucky winner of the 50/50 Raffle Ticket was ?????. Everyone present was a winner in our hearts and minds.

Submitted by Sherlene Y. Bradbury, G.G.

Photos by Melanie A. Marts, G.G.

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