( Fr- jade; Ger- Jadeit; Nor- jadeitt; Rus- )
JADE (jadeite), Na (Al,Fe)Si2O6.
A. Jadeite nodule, top (height - 8.5 cm)
from Guerrero Negro, Baja California Norte, Mexico. Cal Graeber
Minerals. (© photo by Jeffrey A. Scovil)
B. Jadeite (height - 6.9 cm). Norman Steele collection. (© photo by Jeffrey A. Scovil)C &D. Jadeite. Three-color snuff bottle (height - 7 cm), dated circa 1780-1850. (© photo courtesy of S. Bernstein & Co. San Francisco, www.bernsteinjadeart.com ) The carving on this snuff bottle is described as follows: "two sages cormorant fishing among lily pads during the springtime. The artist has used the natural coloration of the original jadeite boulder masterfully. The colors depicted are emerald green, white and gray-black. The relief work is well rendered with a high degree of polish which is the result of the application of chamois or deer skin repeatedly on to the surface." (© photo courtesy of S. Bernstein & Co. San Francisco, www.bernsteinjadeart.com)
E. Jadeite (width - 2.8 cm). Norman Steele collection. (© photo by Jeffrey A. Scovil)
DESCRIPTION: Pyroxene jade consists wholly or largely of microcrystalline,
typically blocklike grains of jadeite. The size and
arrangement of the
grains appears to account for the unusual toughness of this jade and
also its relatively common grainy or dimpled appearance, which is
evident when fractured surfaces are viewed with a handlens or simple
microscope. Guatemalan jadeite, which is somewhat atypical, tends
to be relatively coarse grained, commonly including grains large enough
to be seen with the naked eye; in addition, some of it includes
chromium-bearing minerals such as macroscopically discernible
Some jadeitic jade --
e.g., that from the famous Myanmar (formerly Burma) localities
-- contains noteworthy amounts of other minerals such as acmite,
albite, analcime, edenite, diopside, enstatite, kosmochlor, muscovite,
natrolite, nepheline, prehnite, richterite, tremolite and wollastonite.
Geologists, in particular, refer to these impure jades by special names
-- e.g., those with noteworthy amounts of diopside and/or
which are typically dark green or nearly black, are often termed chloromelanite. See THE JADES entry for colors and some of the other
properties that pertain to both Nephrite and Jadeite jade.
H. 6½ - 7 (typically slightly harder than nephrite)
Light transmission - subtransparent to opaque
Luster - ranges from glassy to oily or porcelaneous
Miscellany - many jade boulders have reddish, yellowish, orangy or brownish rinds.
OTHER NAMES: Scores of names have been applied to jadeite jade. Jill Walker in the tome edited by Keverne (1992) lists "common trade names" (i.e., both adjectives and complete designations for jadeite jade) as follows:
OCCURRENCES: Diverse -- e.g., in sequences of chiefly sedimentary rocks that have undergone relatively low-grade metamorphism and as dikes (lenses?) in serpentinites -- with less than a consensus among geologists so far as conclusions relating to their geneses; and as alluvial boulders derived from bedrock occurrences. Ou Yang (2003) lists the following occurrence designations: New Mine skinless stone ("unweathered ... in primary ... deposits"), Mountain stone (in mass wasting environments), Surface Water stone (angular pieces in rivulets), River stone (rounded stones in river beds), and Terrace stone (stones of whatever origin now occurring in terrace deposits). She also lists the following categories based on the common skins or crusts on these stones: Sandy skin (of various colors), water ("feels smooth") skin, and enamel skin.
NOTEWORTHY LOCALITIES: Tawmaw plateau -- e.g., from Hpakan district, near the Uru River, about 65 miles from Mogaung, northern Myanmar (formerly Burma); and near Manzanal, Motagua Valley, Guatemala. Shigley et al. (2000) tabulate localities and pertinent references for localities from which jadeite was recovered during the 1990s. One recently discovered (rediscovered?!!) jadeite deposit seems especially noteworthy: Translucent blue and blue-green jadeite, which closely resembles that apparently used for millenia, by pre-Columbian Mesoamerican Olmecs, was so-to-speak unearthed in 1998. -- A major hurricane-promoted flooding of the Motagua River of Guatemala, and consequent landslides moved large "bus-size boulders of Olmec blue jade" to, for example, river beds, where they were washed clean; in addition, the movements exposed jadeite veins here and there in the bedrock (Broad, 2002). Shigley et al. (2010, p. 210) include several world-wide localities in their list "localities of the 2000s."
REMARKS: As already noted, some jade in the marketplace has been dyed, chemically bleached, coated with paraffin, wax or some resin and/or impregnated by a polymer (Fritsch et al., 1992). Other known treatments, used singly, together, or along with those just mentioned include vacuuming, the application of acid (commonly acetic acid) or a bleach to remove extraneous stains or other coatings, and heating to improve colors. The impregnation has been used to so-to-speak make the matieral more stable. On the other hand, and quite remarkably -- in fact, in my opinion, ridicuously -- some of the dyeing has involved differential application of the dyes purportedly to make the jade take a "more natural appearance." -- Wow! See also McClure, Kane and Sturman, 2010, p.234.
In general, jadeite jade, unlike some nephrite jade, does not become dull with the passage of time.
It seems a bit ironic that the designation China
jade is sometimes used in an almost generic way to refer to
jadeite jade even though most jade pieces from China are nephrite jade.
reported that "Doubly Fortunate," an intense green jadeite necklace was
sold at a Christie's auction for nine million, 300 thousand
(i.e., 9.3 million) dollars. (Anon., 2014).
A jadeite boulder, reported to be the largest ever found, is on display in front of the Myanmar Gems Enterprise headquarters at Yangon, Myanmar (Koivula, Kammerling and Fritsch, 1992, p. 132). Apparently recovered from the Khy-Siu mine in the Mogaung area of Myanmar (formerly Burma) in July of 1982, the boulder has a circumference of 8.75 meters (~29 feet) and has been calculated to weigh about 33 metric tons (36 tons).
SIMULANTS, etc.: See those given in THE
introductory entry. In addition, it seems noteworthy that some
items fashioned from nephrite jade have been marketed as jadeite.
***Synthetic jade - "General Electric (GE)
Gem Technology has developed a proprietary process for manufacturing
synthetic jadeite . . . The samples [supplied the GIA Gem Trade
Laboratory] ranged in color and quality ... but the finest
green material rivaled 'Imperial' jade . . . [this .
synthesis is said to be] achieved in a high pressure environment .
. . [and] The gemological properties of the small number of samples
we have tested
to date overlap those of natural jadeite." (Moses, in Moses et al.,
2002). See also
Renfro et al. (2011).
of less that top quality has been coated with an organic polymer that
improves its color and overall appearance has been reported by
Zhang, Lu and Chen (2013). This material can be distinguished
from non-coated jadeite in several ways. For example, "Coated
jadeite feels dray and rough..., feels warm, unlike the smooth, cold
surface of uncoated jadeite.., [has a] .the Mohs hardness [of ~]
3..., and ( often display[s] ...traces of scratching (op. cit. p.
REFERENCE: Hargett, 1990; Lu, 2012; Ou Yang, 2003.
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