The only two gemrocks accepted as "Jade" worldwide are: Jadeite Jade and Nephrite Jade. They belong to two different mineral groups whose individual members can be very similar in appearance..

Jadeite Jade

Jadeit

Jadeite jade sculpture

Image: K. Sieber, www.makrogalerie.de

Jadeite is a member of the pyroxene group. A growth characteristic of this mineral is that it forms a monomineralic rock, with a large number of mineral grains closely intergrown. As a result, jadeite rocks are of exceptional toughness.

The most desirable color of jadeite jade is an intense green caused by chromium. In addition, there are numerous color varieties such as white, black, yellow, pink, red, brown and red-violet (»Lavender Jade«).

Green jadeite comes on the market in 3 grades of quality:

  •     The best quality is called Imperial Jade or Grade A-Jade (A-Jade for short). It has a strong green color and is translucent.
  •     B-Jade is boiled in strong acids to remove impurities (such as iron oxides) from the cracks and sealed with wax or synthetic resin.
  •     C-Jade is treated like B-Jade and additionally dyed green.

Nephrite Jade

»Nephrite« is a variety name for minerals from the amphibole group, more precisely from the (ferro-) actinolite - tremolite solid solution series. Nephrite differs from the crystalline green actinolite by its matted fibrous structure. The color caused by iron and/or chromium ranges from yellowish beige ("mutton fat jade"), greenish gray ("celadon jade") over dark green to almost black.

Nephrite - just like jadeite - can be bleached and colored. Not infrequently, open cracks are sealed with synthetic resin (see: Fissure fillings in gemstones).

 

Imitationen

The correlations of chemical and physical properties presented in the EPI article What is »JADE« ? open a wide field for "interpretations". A large part of the "Jade" offered in the trade consists neither of Jadeite-Jade nor of Nephrite-Jade and also does not have their properties. One gets the impression that every green and opaque mineral is traded as "jade" sooner or later. In addition, there are always attempts to market new minerals and rocks under this name.

 

Serpentine

Serpentinit

Ship made of serpentinite rock

Image: K. Sieber, www.makrogalerie.de

Similar to "pyroxene" and "amphibole", "Serpentine" is a name for a whole group of minerals. Among others, the minerals antigorite, chrysotile and lizardite belong to the serpentine group. When they form rocks, they are called serpentinite. This is usually the case with the serpentine minerals used as jade imitations. The serpentinite rocks offered as "China Jade" or "New Jade" not only look like real jade, in some deposits they also occur together with nephrite jade.

As a rule, the minerals of the serpentine group are much softer than jadeite or nephrite. Antigorite (formerly called "bowenite"), however, can reach almost the hardness of nephrite (Mohs hardness 5-6). However, the toughness is far below that of true jade. Due to its much easier workability, this group of minerals has risen to become the preferred jade substitute in recent years. Art objects like vases, bowls, sculptures, but also jewelry and necklaces: Many offers of this kind are serpentinite and not »Jade«.

Glasses

Other jade imitations consist of glasses that have been "devitrified" using a special process. This gives them small inclusions and makes them cloudy to almost opaque.

Jadeit Imitation Glas

Jadeite imitation made of artificial glass

Jadeit Imitation

The typical gas bubbles of a glass can be seen in the magnification (mouseover to enlarge)

Images: K. Sieber, www.makrogalerie.de

These artificial products are very successfully marketed under the trade names "Siberian Jade", "Metajade", "Victoria Stone", "Iimori Stone" or "Kinga Stone".

Table of jade imitations

deceptive name identity
African Jade Diopsid-Quarzit
Alabaster Jade Gips
Alaska Jade Pektolith-Gestein
Amazonas Jade (Amazonit)-Feldspat
Amerikanische Jade Vesuvianit (Californit)
Anden Jade Serpentinit
Australische Jade grüner Chalcedon
Baikal Jade Serpentin (Antigorit)
Californische Jade Vesuvianit (Californit)
China Jade Serpentin (Antigorit)
Colorado Jade (Amazonit)-Feldspat
Dushan Jade Saussurit-Gestein
Feuer Jade gewöhnlicher Opal
Fujian Jade Speckstein (Talk)
Fukien Jade Speckstein (Talk)
Granat Jade Grossularit
Henan Jade (Aventurin-) Quarzit
Hidaka Jade Cr-Diopsid reiches Gestein
Honan Jade Speckstein (Talk)
Hsui Yen grüner Jaspis
Imperial Mexican Jade grün gefärbter Calcit
Indische Jade (Aventurin-) Quarzit
Jade Matrix Amphibol-Gestein
Jade Tenace Saussurit-Gestein
Jadeolit Syenit-Gestein
Japanische Jade Prehnit / Baumachat
Jaspis Jade grüner Jaspis
Korea Jade Serpentin (Antigorit)
Longxi Jade Tremolit Fels
Malachite Jade Diopsid-Quarzit
Malayische Jade (gefärbter) Quarzit
Manchurian Jade Talk, Speckstein
Marble Bar Jade Serpentin / Chlorit
Meta-Jade Glas (Kunstprodukt)
Mexikanische Jade Kalkstein, grün gefärbt
Nanyang Jade grüner Chalcedon
Neue Jade Serpentin (Antigorit)
New Zealand Jade Serpentin (Antigorit)
Norwegische Jade Serpentin (Lizardit)
Oceanic Jade Serpentinit
Oregon Jade Chalcedon (Plasma) | Jaspis
Pakistan Jade Vesuvianit
Pate de Riz Glas (Kunstprodukt)
Pektolith Jade Pektolith
Pilbara Jade Serpentin / Chlorit
Pseudojade Serpentin (Antigorit)
Qilian Jade Serpentinit
Queensland Jade grüner Chalcedon (Chrysopras)
Rare Jade Hydrogrossular
Regal Jade (Aventurin-) Quarzit
Rhode Island Jade Serpentin (Antigorit)
Rhodesische Jade Verdit (Fuchsitgestein)
Rosa Jade rosa Zoisit (Thulit)
Rote Jade rötlicher Quarzit / Karneol
Rote Peking Jade Rhodonit
Schneeflocken Jade Tremolit-Albit-Gestein
Schweizer Jade (gefärbter) Jaspis / Nephrit / Saussurit
Serpentin Jade Serpentin (Antigorit)
Shanghai Jade Speckstein (Talk)
Sibirische Jade Serpentin (Antigorit)
Sillimanit Jade Sillimanit grün
Silver Jade (Aventurin-) Quarzit
Silver Peak Jade Malachit
Souchow Jade Serpentin (Antigorit) / Speckstein
Steirische Jade Klinochlor-Serpentin-Gestein
Südafrikanische Jade Grossularit
Südpazifik-Jade Chrysopras
Transvaal Jade Hydrogrossularit
Ural Jade Serpentin (Antigorit)
Vesuvianit Jade Vesuvianit (Californit)
Victoria Jade Glas (Kunstprodukt)
Weiße Jade Hydrogrossular / Calcit / Nephrit
Wyoming Jade Tremolit-Albit-Gestein
Xinyi Jade Serpentinit
Xiuyan Jade Serpentinit

 

If you think that most jade imitations are mentioned now, you are wrong!

 

Jadeit Imitation Quarzit

Jade imitations from colored quartzite are very common

Image: K. Sieber, www.makrogalerie.de

Besides the imitations with special trade names mentioned in the table, a variety of other minerals that have not been given a special name are in the race for the favor of jade buyers. The most important of these are: Agalmatolite (a very soft soapstone-like rock), green opaque fluorite, colored quartzite, and wollastonite; Saussurite (a fine-grained mixture of numerous weathering minerals), Sillimanite, and Verdite (a mica rock).

For all these imitations it is true: they may look very similar to real "jade", but are easily identifiable by a precise gemmological examination.

Ref.:
Henn & Pintar, Gemmologie, Zeitschrift der DGemG, 46/2/1997: Jade - Verwechslungsmöglichkeiten, Imitationen und künstliche Eigenschaftsveränderungen

 


Autor: Dipl.-Min. B. Bruder

© INSTITUT FÜR EDELSTEIN PRÜFUNG (EPI), 2020

 

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