Difference between revisions of "Nephrite"

From The Gemology Project
Jump to: navigation, search
(addition from Robert Biehl (id:431))
(Sources consulted)
Line 15: Line 15:
 
==Sources consulted==
 
==Sources consulted==
 
*Smithsonian Handbooks, Gemstones, Second Edition 2002
 
*Smithsonian Handbooks, Gemstones, Second Edition 2002
 +
== G&G Articles on Jade 1934-1980==
 +
The GIA has published all the [http://www.gia.edu/research-resources/gems-gemology/back-issue-archive/index-back-issues-1934-80.html G&G's from 1934 until 1980 online]. The organization of the list by subject was done by [http://archive.org/details/GillsHistoricalIndexToGemsAndJewelryOnline-ByJosephO.Gill2009in Joseph Gill].
 +
 +
<ul><li>[http://www.gia.edu/research-resources/gems-gemology/back-issue-archive/Mar-Apr-1934.pdf March-April 1934, <b>Jadeite thought found in America (Oregon)</b>, p. 54, 1p.]
 +
</li><li>[http://www.gia.edu/research-resources/gems-gemology/back-issue-archive/May-June-1934.pdf">May-June 1934, <b>Jade</b>, p. 80, 3pp.</a>
 +
</li><li>[http://www.gia.edu/research-resources/gems-gemology/back-issue-archive/May-June-1934.pdf May-June 1934, <b>Red Jade, by M. Ehrmann</b>, p. 84, 1p.]
 +
</li><li>[http://www.gia.edu/research-resources/gems-gemology/back-issue-archive/fall-1944.pdf Fall 1944, <b>Nephrite found in Lander</b>, Wyo., in 1936, p. 170, 1p.]
 +
</li><li>[http://www.gia.edu/research-resources/gems-gemology/back-issue-archive/fall-1948.pdf Fall 1948, <b>Jade Carving in China</b>, p. 82, 5pp.]
 +
</li><li>[http://www.gia.edu/research-resources/gems-gemology/back-issue-archive/spring-1950.pdf Spring 1950, <b>Jadeite and nephrite found in Calif</b>., p. 289, 1p.]
 +
</li><li>[http://www.gia.edu/research-resources/gems-gemology/back-issue-archive/summer-1951.pdf Summer 1951, <b>Jadeite and nephrite found in Calif., and artifacts</b>, p. 76, 3pp.]
 +
</li><li>[http://www.gia.edu/research-resources/gems-gemology/back-issue-archive/spring-1952.pdf Spring 1952, <b>Jade in Mexico</b>, p. 147, 5pp.]
 +
</li><li>[http://www.gia.edu/research-resources/gems-gemology/back-issue-archive/summer-1954.pdf Summer 1954, <b>The Nature of Ja</b>de, p. 38, 9pp.]
 +
</li><li>[http://www.gia.edu/research-resources/gems-gemology/back-issue-archive/fall-1956.pdf Fall 1956, <b>Jadeite from San Benito County, Calif.,</b> p. 331, 4pp.]
 +
</li><li>[http://www.gia.edu/research-resources/gems-gemology/back-issue-archive/fall-1960.pdf Fall 1960, <b>Jade Cutting Today</b>, p. 81, 9pp.]
 +
 +
</li><li>[http://www.gia.edu/research-resources/gems-gemology/back-issue-archive/winter-1964.pdf Winter 1964, <b>"Pigeon eye" nephrite from Wyoming</b> (shows chatoyant spots), p. 251, 2pp.]
 +
</li><li>[http://www.gia.edu/research-resources/gems-gemology/back-issue-archive/summer-1966.pdf Summer 1966, <b>Taiwan jade (nephrite)</b>, p. 62, 1p.]
 +
</li><li>[http://www.gia.edu/research-resources/gems-gemology/back-issue-archive/spring-1976.pdf Spring 1976, <b>Jade, China's Contribution to Fine Art</b>, by A. Alexander, p. 145, 8pp.]
 +
</li><li>[http://www.gia.edu/research-resources/gems-gemology/back-issue-archive/fall-1979.pdf Fall 1979, <b>Clarification of Composition of Maw Sit Sit</b>, p. 217, 2p.]
 +
</li><li>[http://www.gia.edu/research-resources/gems-gemology/back-issue-archive/summer-1980.pdf Summer 1980, <b>Australia Likely To Be Major Supplier of Jade</b>, by J. Stone, p. 331, 1p.]
 +
</li></ul>

Revision as of 15:59, 20 August 2012

Nephrite
Chemical composition Complex Ca Mg/Fe (calcium magnesium/iron) silicate
Crystal system Monoclinic
Habit Polycrystalline
Fracture Splintery
Hardness 6.5
Refractive index ±1.62
Specific gravity 2.90 - 3.20
Lustre Greasy to vitreous

Nephrite has been recognized as a separate type of jade since 1863. It is formed from aggregates of fibrous amphibole crystals. The structure they form is interlocking and tougher than steel. It's colors range from dark green iron rich varieties to cream colored magnesium rich varieties. It can be found blotchy, banded or singly colored. It is vary popular for carving and was used for weapons of the past.

Enhancements

Common enhancements to nephrite:

  • Fracture filling - wax - conceal cracks and fractures
  • Coatings - wax - to improve luster

Occurrence

Nephrite is found in Turkestan, Myanmar, Siberia (dark green rocks with black spots), Russia, China, New Zealand, Australia (black stones), USA, Canada, Mexico, Brazil, Taiwan, Zimbabwe (dark green), Italy, Poland, Germany and Switzerland. It has been carved by the Chinese for at least 2,000 years.

Sources consulted

  • Smithsonian Handbooks, Gemstones, Second Edition 2002

G&G Articles on Jade 1934-1980

The GIA has published all the G&G's from 1934 until 1980 online. The organization of the list by subject was done by Joseph Gill.