Post by 1dave on May 31, 2014 1:09:23 GMT -5
An extension of Geology for Rockhounds.
Jade Buddha
The jade story began in deep ocean bottoms as mantle materials, iron and magnesium, were volcanically extruded into sea water.
It is a 3 step process.
Step 1. Magma crystallizes as olivine basalt, pyroxene and chlorite.
Step 2. Seawater modifies them while still hot into serpentine.
Samples of the oceanic crust and uppermost mantle from ocean basins document that their ultramafic rocks commonly contain abundant serpentine, 2Mg3Si2O5(OH)4.
HotRocks4.JPG
Mantle Magma becomes Olivine Basalt and pyroxene, then serpentine, and finally Jade!
There are three important mineral polymorphs of serpentine: antigorite, chrysotile and lizardite.
Antigorite is the polymorph of serpentine that most commonly forms during metamorphism of wet ultramafic rocks and is stable at the highest temperatures—to over 600 °C at depths of around 60 km. In contrast, lizardite and chrysotile typically form near the Earth's surface and break down at relatively low temperatures, probably well below 400 °C.
The chrysotile group of minerals are polymorphous. Chrysotile with a fibrous habit is one type of asbestos. Other minerals in the chrysotile group may have a platy habit.
Serpentine-LizarditeTexture.jpg
Alterations may be incomplete, causing physical properties of serpentines to vary widely.
Most serpentines are opaque to translucent, light (specific gravity between 2.2–2.9), soft (hardness 2.5–4), infusible and susceptible to acids. All are microcrystalline and massive in habit, never being found as single crystals. Luster may be vitreous, greasy or silky. Colors range from white to grey, yellow to green, and brown to black, and are often splotchy or veined. Many are intergrown with other minerals, such as calcite and dolomite.
Serpentine occurrence is worldwide. notable localities are:
British Colombia and New Caledonia, Canada (Quebec), USA (northern California, Rhode Island, Connecticut, Massachusetts, Maryland and southern Pennsylvania), Guatemala, Afghanistan, Britain (Cornwall and Ireland), Greece (Thessaly), China, Ural Mountains (Russia), France, Korea, Austria (Styria and Carinthia), India (Assam, and Manipur), Myanmar (Burma), New Zealand, Norway and Italy.
Step 3. Instead of being subducted, masses of ocean bottom serpentine are vised between continental mountains, where the high pressure but low temperature collisions transmogrify some of the serpentines into nephrite amphibole or jadeite pyroxene, depending on what elements are present.
All Jades are only found in serpentine rich areas.
Because of its extreme toughness in contrast to the weaker material it forms in (serpentine), jade is nearly always found as weathered boulders and cobbles in stream deposits or glacial sediment.
The easiest way to distinguish jade from other boulders in the field is with a hammer. The hammer will harmlessly ricochet off jade. Listen for a high pitched “ping” instead of the ripe melon “thunk” sound of most rocks.
The term “jade” is properly applied by gemmologists to only two different metamorphic rocks, Nephrite (calcite/magnesium) and Jadeite (sodium/aluminum), both composed of silicate minerals. Both characteristically form very tough, fine grained rocks. Both are inosilicates, characterized by chains of silica tetrahedra. Highly valued from pre-historic times for its beauty and durability, jade is usually a greenish black to creamy white ornamental stone or gemstone. Translucent emerald-green jadeite-jade is the most prized variety. Jadeite is also found in blue, lavender-mauve and pink in color, depending on mineralogy and impurity elements.
Jadeite has about the same hardness as quartz. Nephrite is slightly softer, but is tougher than jadeite.
NOTE: Probably even though there was more magnesium in the original material, and perhaps because there is more calcium than sodium in the earth’s crust, there has been far more nephrite found over the centuries than jadeite, making rare fine jadeite the more valuable of the two.
Jadeite, Na(Al; Fe )Si2O6, belongs to the pyroxene group, a silicate of sodium and aluminum.
PyroxeneChains-1.jpg
Pyroxenes may be simple oxygen-linked strings or complex double chains latterly bonded to various positively charged atoms that produce differing mineral species.
The pyroxenes have single chain structures as in jadeite, diopside, enstatite, and spodumene.
Jadeite (7) is harder than nephrite, but not as tough.
Nephrite, Ca2(Mg, Fe)5Si8O22(OH)2, belongs to the amphibole group, a silicate of calcium and magnesium.
AmphiboleChains-1.jpg
with some iron in the ferrous state, a tremolite and/or actinolite-rich rock. The amphiboles have double-chain structures as in nephrite, hornblende, tremolite, and actinolite.
Nephrite (6.5) is softer than jadeite, but tougher.
Although examination for felted texture with a 10X loupe is helpful, and tapping and listening for a “ping” may eliminate some fake jades, it is difficult to impossible to distinguish nephrite jade from jadeite jade by visual inspection.
Specific gravity determination is the most reliable of simple identification methods for distinguishing the two from other rocks. If you are serious, purchase LST for a mere $127/lb call Central Chemical Consulting, email: info@heavyliquids.com
lst_bottle_1.jpg
Rough minerals from the two groups can be distinguished by cleavage: 56° for the amphiboles (tremolite) and 90° for the pyroxenes (diopside). Both jadeite and nephrite are monoclinic.
It should be noted that pyroxenes are anhydrous, while amphiboles contain water and will give off water vapor or steam when heated in a closed test-tube. Also of value is the fact that the amphiboles tend to be fibrous, acicular or elongated in habit.
NephriteJadeDragon.jpg
Nephrite Dragon
Nephrite Jade:
Nephrite is a metamorphic rock (probably metamorphosed calcium rich Gabbro) comprised primarily of massive microcrystalline to cryptocrystalline felted amphiboles of the tremolite - actinolite series. The matted chain and ribbon structure of nephrite jade makes it one of the toughest, but far from the hardest mineral known. It was probably recognition of this property that induced the world's ancient peoples to utilize it for the making of blades, choppers, bowls, vases, and carved images.
Nephrite density is about 2.95 - 3.33 g/cc, RI: 1.600 - 1.627, Birefringence: .027
Nephrite consists of a microcrystalline interlocking fibrous matrix of the calcium, magnesium-iron rich amphibole mineral series tremolite (calcium-magnesium)-ferroactinolite (calcium-magnesium-iron). The middle member of this series with an intermediate composition is called actinolite (the silky fibrous mineral form is one form of asbestos).
Found in mutton fat white through various shades of green, the higher the iron content, the greener the color.
In addition to amphibole, nephrite can contain minor to trace amounts of diopside, grossularitic garnet, magnetite, chromite, graphite, apatite, rutile, pyrite, datolite, vesuvianite, prehnite, talc, the serpentine polymorphs and titanite.
White nephrite, termed white jade or mutton-fat jade, is nearly pure tremolite, while most nephrite is green owing to the Fe content in actinolite. Chromium colors nephrite emerald green, while iron oxides and hydroxides introduced along grain boundaries stain it yellow to brown.
Nephrite does not generally accept an even polish, probably due to the presence of other minerals and variations in the felting crystal structure. The more densely random matted areas take a higher polish than less tightly matted areas.
Some nephrite areas still consist of parallel tremolite fibers that give a cat’s eye chatoyancy.
JadeiteDragon.JPG
JadeiteDragon
Jadeite Jade:
Jadeite is a metamorphic rock (probably metamorphosed sodium rich Diorite) composed primarily of a sodium and aluminum rich pyroxene. The gem form of the mineral is a microcrystalline interlocking crystal matrix with a fine granular structure of interlocking crystals that may vary slightly in hardness. This gives rise to a subtly dimpled surface when the material is cut and polished. The use of diamond in the polishing process makes the dimpling much less apparent.
Jadeite has a density of about 3.20-3.33 and will remain suspended or very slowly sink in methylene iodide (di-iodomethane). Its mean R.I. is 1.66 (alpha 1.654; gamma 1.667).
With a hardness of 7 on the Mohs' scale of relative hardness, jadeite occurs in more color variations than nephrite. White, grey, blue, lavender, yellow, mutton-fat cream, orange, brown, burnt-sienna red, black and, of course, green from the palest of greens to a deep translucent emerald hue if chromium is present.
Jadeite jade is found exclusively as nodular or lens-shaped masses in serpentinite rocks that have undergone metamorphism at high pressures but relatively low temperatures.
Nephrite jade, which is also a product of metamorphism plus fluid infiltration, is much more widespread. It is also found in association with serpentinite in all known localities.
Over a billion years ago as the super continent of Rodinia was being formed, jade was being made.
Archean Rocks.jpg
640 million years ago Rodinia split in half as the Pacific ocean was born.
around 600 million years ago, the northern half of a great collision zone called the East African Orogeny formed the Arabian-Nubian Shield. This collision zone formed near the end of Neoproterozoic time when East and West Gondwana collided to form the supercontinent Gondwana. Jade was being made.
600_1st.jpg
444 Ma The Caledonian orogeny occured as eastern N American mountains were formed, Jade was made.
440_1st.jpg
around 360 million years ago, Euramerica and Gondwana were beginning to converge to create what would become known as the supercontinent Pangaea. Jade was being made.
370_1st.jpg
200 million years ago Pangea began to break apart. as The Atlantic ocean began to form.
80 million years ago in a more modern looking world, more Jade was made.
080_1st.jpg
Historically and presently important jade producing localities are:
LOCATIONS:
Australia
South Australia, Eyre Peninsula, Cowell Jade Province [var: Nephrite] Nichol (2000)
Burma (Myanmar)
Kachin State, Mohnyin District (Moe Hnyin District), Hpakant-Tawmaw Jade Tract
Phakant Mine [var: Jadeite] Ou Yang (1999)
Lonkin [var: Jadeite] Ou Yang (1999)
Maw-Sisa [var: Jadeite] Ou Yang (1999)
Sate Mu (Sine Naung) [var: Jadeite] Ou Yang (1999)
Seng Tong [var: Jadeite] Ou Yang (1999)
Tawmaw (Tawhmaw; Taw Maw) [var: Jadeite] Ou Yang (1999)
Mohnyin Township (Moe Hnyin Township), Mawhun [var: Jadeite] Ou Yang (1999)
Sagaing Division, Hkamti District, Nansibon mining district
(Namsibum; Manhsibon; Manshibon; Namsipon) [var: Jadeite] Ou Yang (1999)
Natmaw (Nawmaw; Nathmaw) [var: Jadeite] Ou Yang (1999)
Canada
British Columbia, Liard Mining Division, Cassiar Mine [var: Nephrite] Nichol (2000)
Dease Lake [var: Nephrite] Nichol (2000)
China
The Kunlun or Kuen-Lun Mountains are the original "Jade Mountains" of China. White and greenish nephrite jade is found in small quarries and as pebbles and boulders in the rivers flowing from the Kuen-Lun mountain range eastward into the Takla-Makan desert area. The river jade collection is concentrated in the Yarkand, the White Jades (Yurungkash) and Black Jade (Karakash) Rivers.
the Ningshao area in the Yangtze River Delta (Liangzhu culture 3400–2250 BC)
the Liaoning province and Inner Mongolia (Hongshan culture 4700–2200 BC).[
Dushan Jade was being mined as early as 6000 BC.
Cuba
Guantánamo Province, Sierra del Convento [var: Jadeite] Garcia-Casco et al. (2009)
Guatemala, Motagua River banks [var: Jadeite] William J. Broad (2000)
Italy
Liguria, Genova Province, Sestri Levante
Libiola Mine [var: Nephrite] Nichol (2000)
Japan
Honshu Island, Chubu Region, Niigata Prefecture, Itoigawa City
Hime River (Himekawa) [var: Jadeite] Chihara (1999)
Kotaki River (Kotakigawa) [var: Jadeite] Chihara (1999)
Kazakhstan
Karagandy Province (Qaragandy Oblysy; Karaganda Oblast')
Balkhash Region (Balqash; Karatas; Prebalkhashie)
Krasnyi Oktyabr', Itmurundy massif (Itmuryndy) [var: Jadeite] Spiridonov (1998)
Russia
Eastern-Siberian Region
Krasnoyarsk Territory (Krasnoyarsk Kray; Krasnoyarskii Krai)
Sayan Mts, Western Sayan range
Borusskoe deposit (Kashkarakskoe) [var: Jadeite] Spiridonov (1998)
Western-Siberian Region
Polar Urals, Nenetskiy Autonomous Okrug
Kharp, Pusyerka (Lot 88) [var: Jadeite] Yushkin (1996)
Switzerland
Grischun (Grisons; Graubünden), Puschlav (Poschiavo Valley)
Selva, Scortaseo (Scurtaseu) [var: Nephrite] Nichol and Giess (2005)
Taiwan
Taiwan Province
Hualien Co., Fengtien nephrite belt [var: Nephrite] Adams and Beck (2009)
Turkey
Marmara Region, Bursa Province
Tavs,anl Zone, Orhaneli [var: Jadeite] Okay (2002)
USA
California, Monterey Co., Santa Lucia Mts (Santa Lucia Range)
Los Burros District, Plaskett, Cape San Martin, Jade Cove
Cape San Martin prospect (Jade Cove prospect) [var: Nephrite] Paradise (1985)
Wyoming
Fremont Co., Granite Mts [var: Nephrite] Ward (1999)
Fake Jade
Buyer Beware! A great variety of imitations are wishfully or fraudulently offered. Amazonite, dyed chalcedony, glass, green quartz, grossular garnet, plastic, prehnite, serpentine, Talc (soapstone), vesuvianite (californite), and others. All can have colors remarkably similar to jade, but jade properties, particularly toughness and specific gravity, can be used to distinguish them.
Jade may be enhanced, sometimes called "stabilized". Some merchants will refer to these as Grades, but it is important to bear in mind that the degree of enhancement is different from color and texture quality. Type A jadeite is not enhanced but can have poor color and texture.
There are three main methods of enhancement known as the ABC Treatment Template:
Type A jadeite has not been treated in any way except surface waxing.
Type B treatment involves exposing a promising but stained piece of jadeite to chemical bleaches and/or acids and impregnating it with a clear polymer resin. This results in a significant improvement of transparency and color of the material. Currently, infrared spectroscopy is the most accurate test for the detection of polymers in jadeite.
Type C jade has been artificially stained or dyed. The effects are somewhat uncontrollable and may result in a dull brown. In any case, translucency is usually lost.
B+C jade is a combination of B and C: it has been both impregnated and artificially stained.
Type D jade refers to a composite stone such as a doublet, a jade top with a plastic backing.
Dyed jade can be most easily distinguished from undyed jade by examination with a Chelsea filter; undyed jadeite will not show the red color of dyed jadeite or nephrite when looked at through the filter.
ChelseaFilter-02.JPG
Jade Buddha
The jade story began in deep ocean bottoms as mantle materials, iron and magnesium, were volcanically extruded into sea water.
It is a 3 step process.
Step 1. Magma crystallizes as olivine basalt, pyroxene and chlorite.
Step 2. Seawater modifies them while still hot into serpentine.
Samples of the oceanic crust and uppermost mantle from ocean basins document that their ultramafic rocks commonly contain abundant serpentine, 2Mg3Si2O5(OH)4.
HotRocks4.JPG
Mantle Magma becomes Olivine Basalt and pyroxene, then serpentine, and finally Jade!
There are three important mineral polymorphs of serpentine: antigorite, chrysotile and lizardite.
Antigorite is the polymorph of serpentine that most commonly forms during metamorphism of wet ultramafic rocks and is stable at the highest temperatures—to over 600 °C at depths of around 60 km. In contrast, lizardite and chrysotile typically form near the Earth's surface and break down at relatively low temperatures, probably well below 400 °C.
The chrysotile group of minerals are polymorphous. Chrysotile with a fibrous habit is one type of asbestos. Other minerals in the chrysotile group may have a platy habit.
Serpentine-LizarditeTexture.jpg
Alterations may be incomplete, causing physical properties of serpentines to vary widely.
Most serpentines are opaque to translucent, light (specific gravity between 2.2–2.9), soft (hardness 2.5–4), infusible and susceptible to acids. All are microcrystalline and massive in habit, never being found as single crystals. Luster may be vitreous, greasy or silky. Colors range from white to grey, yellow to green, and brown to black, and are often splotchy or veined. Many are intergrown with other minerals, such as calcite and dolomite.
Serpentine occurrence is worldwide. notable localities are:
British Colombia and New Caledonia, Canada (Quebec), USA (northern California, Rhode Island, Connecticut, Massachusetts, Maryland and southern Pennsylvania), Guatemala, Afghanistan, Britain (Cornwall and Ireland), Greece (Thessaly), China, Ural Mountains (Russia), France, Korea, Austria (Styria and Carinthia), India (Assam, and Manipur), Myanmar (Burma), New Zealand, Norway and Italy.
Step 3. Instead of being subducted, masses of ocean bottom serpentine are vised between continental mountains, where the high pressure but low temperature collisions transmogrify some of the serpentines into nephrite amphibole or jadeite pyroxene, depending on what elements are present.
All Jades are only found in serpentine rich areas.
Because of its extreme toughness in contrast to the weaker material it forms in (serpentine), jade is nearly always found as weathered boulders and cobbles in stream deposits or glacial sediment.
The easiest way to distinguish jade from other boulders in the field is with a hammer. The hammer will harmlessly ricochet off jade. Listen for a high pitched “ping” instead of the ripe melon “thunk” sound of most rocks.
The term “jade” is properly applied by gemmologists to only two different metamorphic rocks, Nephrite (calcite/magnesium) and Jadeite (sodium/aluminum), both composed of silicate minerals. Both characteristically form very tough, fine grained rocks. Both are inosilicates, characterized by chains of silica tetrahedra. Highly valued from pre-historic times for its beauty and durability, jade is usually a greenish black to creamy white ornamental stone or gemstone. Translucent emerald-green jadeite-jade is the most prized variety. Jadeite is also found in blue, lavender-mauve and pink in color, depending on mineralogy and impurity elements.
Jadeite has about the same hardness as quartz. Nephrite is slightly softer, but is tougher than jadeite.
NOTE: Probably even though there was more magnesium in the original material, and perhaps because there is more calcium than sodium in the earth’s crust, there has been far more nephrite found over the centuries than jadeite, making rare fine jadeite the more valuable of the two.
Jadeite, Na(Al; Fe )Si2O6, belongs to the pyroxene group, a silicate of sodium and aluminum.
PyroxeneChains-1.jpg
Pyroxenes may be simple oxygen-linked strings or complex double chains latterly bonded to various positively charged atoms that produce differing mineral species.
The pyroxenes have single chain structures as in jadeite, diopside, enstatite, and spodumene.
Jadeite (7) is harder than nephrite, but not as tough.
Nephrite, Ca2(Mg, Fe)5Si8O22(OH)2, belongs to the amphibole group, a silicate of calcium and magnesium.
AmphiboleChains-1.jpg
with some iron in the ferrous state, a tremolite and/or actinolite-rich rock. The amphiboles have double-chain structures as in nephrite, hornblende, tremolite, and actinolite.
Nephrite (6.5) is softer than jadeite, but tougher.
Although examination for felted texture with a 10X loupe is helpful, and tapping and listening for a “ping” may eliminate some fake jades, it is difficult to impossible to distinguish nephrite jade from jadeite jade by visual inspection.
Specific gravity determination is the most reliable of simple identification methods for distinguishing the two from other rocks. If you are serious, purchase LST for a mere $127/lb call Central Chemical Consulting, email: info@heavyliquids.com
lst_bottle_1.jpg
Rough minerals from the two groups can be distinguished by cleavage: 56° for the amphiboles (tremolite) and 90° for the pyroxenes (diopside). Both jadeite and nephrite are monoclinic.
It should be noted that pyroxenes are anhydrous, while amphiboles contain water and will give off water vapor or steam when heated in a closed test-tube. Also of value is the fact that the amphiboles tend to be fibrous, acicular or elongated in habit.
NephriteJadeDragon.jpg
Nephrite Dragon
Nephrite Jade:
Nephrite is a metamorphic rock (probably metamorphosed calcium rich Gabbro) comprised primarily of massive microcrystalline to cryptocrystalline felted amphiboles of the tremolite - actinolite series. The matted chain and ribbon structure of nephrite jade makes it one of the toughest, but far from the hardest mineral known. It was probably recognition of this property that induced the world's ancient peoples to utilize it for the making of blades, choppers, bowls, vases, and carved images.
Nephrite density is about 2.95 - 3.33 g/cc, RI: 1.600 - 1.627, Birefringence: .027
Nephrite consists of a microcrystalline interlocking fibrous matrix of the calcium, magnesium-iron rich amphibole mineral series tremolite (calcium-magnesium)-ferroactinolite (calcium-magnesium-iron). The middle member of this series with an intermediate composition is called actinolite (the silky fibrous mineral form is one form of asbestos).
Found in mutton fat white through various shades of green, the higher the iron content, the greener the color.
In addition to amphibole, nephrite can contain minor to trace amounts of diopside, grossularitic garnet, magnetite, chromite, graphite, apatite, rutile, pyrite, datolite, vesuvianite, prehnite, talc, the serpentine polymorphs and titanite.
White nephrite, termed white jade or mutton-fat jade, is nearly pure tremolite, while most nephrite is green owing to the Fe content in actinolite. Chromium colors nephrite emerald green, while iron oxides and hydroxides introduced along grain boundaries stain it yellow to brown.
Nephrite does not generally accept an even polish, probably due to the presence of other minerals and variations in the felting crystal structure. The more densely random matted areas take a higher polish than less tightly matted areas.
Some nephrite areas still consist of parallel tremolite fibers that give a cat’s eye chatoyancy.
JadeiteDragon.JPG
JadeiteDragon
Jadeite Jade:
Jadeite is a metamorphic rock (probably metamorphosed sodium rich Diorite) composed primarily of a sodium and aluminum rich pyroxene. The gem form of the mineral is a microcrystalline interlocking crystal matrix with a fine granular structure of interlocking crystals that may vary slightly in hardness. This gives rise to a subtly dimpled surface when the material is cut and polished. The use of diamond in the polishing process makes the dimpling much less apparent.
Jadeite has a density of about 3.20-3.33 and will remain suspended or very slowly sink in methylene iodide (di-iodomethane). Its mean R.I. is 1.66 (alpha 1.654; gamma 1.667).
With a hardness of 7 on the Mohs' scale of relative hardness, jadeite occurs in more color variations than nephrite. White, grey, blue, lavender, yellow, mutton-fat cream, orange, brown, burnt-sienna red, black and, of course, green from the palest of greens to a deep translucent emerald hue if chromium is present.
Jadeite jade is found exclusively as nodular or lens-shaped masses in serpentinite rocks that have undergone metamorphism at high pressures but relatively low temperatures.
Nephrite jade, which is also a product of metamorphism plus fluid infiltration, is much more widespread. It is also found in association with serpentinite in all known localities.
Over a billion years ago as the super continent of Rodinia was being formed, jade was being made.
Archean Rocks.jpg
640 million years ago Rodinia split in half as the Pacific ocean was born.
around 600 million years ago, the northern half of a great collision zone called the East African Orogeny formed the Arabian-Nubian Shield. This collision zone formed near the end of Neoproterozoic time when East and West Gondwana collided to form the supercontinent Gondwana. Jade was being made.
600_1st.jpg
444 Ma The Caledonian orogeny occured as eastern N American mountains were formed, Jade was made.
440_1st.jpg
around 360 million years ago, Euramerica and Gondwana were beginning to converge to create what would become known as the supercontinent Pangaea. Jade was being made.
370_1st.jpg
200 million years ago Pangea began to break apart. as The Atlantic ocean began to form.
80 million years ago in a more modern looking world, more Jade was made.
080_1st.jpg
Historically and presently important jade producing localities are:
LOCATIONS:
Australia
South Australia, Eyre Peninsula, Cowell Jade Province [var: Nephrite] Nichol (2000)
Burma (Myanmar)
Kachin State, Mohnyin District (Moe Hnyin District), Hpakant-Tawmaw Jade Tract
Phakant Mine [var: Jadeite] Ou Yang (1999)
Lonkin [var: Jadeite] Ou Yang (1999)
Maw-Sisa [var: Jadeite] Ou Yang (1999)
Sate Mu (Sine Naung) [var: Jadeite] Ou Yang (1999)
Seng Tong [var: Jadeite] Ou Yang (1999)
Tawmaw (Tawhmaw; Taw Maw) [var: Jadeite] Ou Yang (1999)
Mohnyin Township (Moe Hnyin Township), Mawhun [var: Jadeite] Ou Yang (1999)
Sagaing Division, Hkamti District, Nansibon mining district
(Namsibum; Manhsibon; Manshibon; Namsipon) [var: Jadeite] Ou Yang (1999)
Natmaw (Nawmaw; Nathmaw) [var: Jadeite] Ou Yang (1999)
Canada
British Columbia, Liard Mining Division, Cassiar Mine [var: Nephrite] Nichol (2000)
Dease Lake [var: Nephrite] Nichol (2000)
China
The Kunlun or Kuen-Lun Mountains are the original "Jade Mountains" of China. White and greenish nephrite jade is found in small quarries and as pebbles and boulders in the rivers flowing from the Kuen-Lun mountain range eastward into the Takla-Makan desert area. The river jade collection is concentrated in the Yarkand, the White Jades (Yurungkash) and Black Jade (Karakash) Rivers.
the Ningshao area in the Yangtze River Delta (Liangzhu culture 3400–2250 BC)
the Liaoning province and Inner Mongolia (Hongshan culture 4700–2200 BC).[
Dushan Jade was being mined as early as 6000 BC.
Cuba
Guantánamo Province, Sierra del Convento [var: Jadeite] Garcia-Casco et al. (2009)
Guatemala, Motagua River banks [var: Jadeite] William J. Broad (2000)
Italy
Liguria, Genova Province, Sestri Levante
Libiola Mine [var: Nephrite] Nichol (2000)
Japan
Honshu Island, Chubu Region, Niigata Prefecture, Itoigawa City
Hime River (Himekawa) [var: Jadeite] Chihara (1999)
Kotaki River (Kotakigawa) [var: Jadeite] Chihara (1999)
Kazakhstan
Karagandy Province (Qaragandy Oblysy; Karaganda Oblast')
Balkhash Region (Balqash; Karatas; Prebalkhashie)
Krasnyi Oktyabr', Itmurundy massif (Itmuryndy) [var: Jadeite] Spiridonov (1998)
Russia
Eastern-Siberian Region
Krasnoyarsk Territory (Krasnoyarsk Kray; Krasnoyarskii Krai)
Sayan Mts, Western Sayan range
Borusskoe deposit (Kashkarakskoe) [var: Jadeite] Spiridonov (1998)
Western-Siberian Region
Polar Urals, Nenetskiy Autonomous Okrug
Kharp, Pusyerka (Lot 88) [var: Jadeite] Yushkin (1996)
Switzerland
Grischun (Grisons; Graubünden), Puschlav (Poschiavo Valley)
Selva, Scortaseo (Scurtaseu) [var: Nephrite] Nichol and Giess (2005)
Taiwan
Taiwan Province
Hualien Co., Fengtien nephrite belt [var: Nephrite] Adams and Beck (2009)
Turkey
Marmara Region, Bursa Province
Tavs,anl Zone, Orhaneli [var: Jadeite] Okay (2002)
USA
California, Monterey Co., Santa Lucia Mts (Santa Lucia Range)
Los Burros District, Plaskett, Cape San Martin, Jade Cove
Cape San Martin prospect (Jade Cove prospect) [var: Nephrite] Paradise (1985)
Wyoming
Fremont Co., Granite Mts [var: Nephrite] Ward (1999)
Fake Jade
Buyer Beware! A great variety of imitations are wishfully or fraudulently offered. Amazonite, dyed chalcedony, glass, green quartz, grossular garnet, plastic, prehnite, serpentine, Talc (soapstone), vesuvianite (californite), and others. All can have colors remarkably similar to jade, but jade properties, particularly toughness and specific gravity, can be used to distinguish them.
Jade may be enhanced, sometimes called "stabilized". Some merchants will refer to these as Grades, but it is important to bear in mind that the degree of enhancement is different from color and texture quality. Type A jadeite is not enhanced but can have poor color and texture.
There are three main methods of enhancement known as the ABC Treatment Template:
Type A jadeite has not been treated in any way except surface waxing.
Type B treatment involves exposing a promising but stained piece of jadeite to chemical bleaches and/or acids and impregnating it with a clear polymer resin. This results in a significant improvement of transparency and color of the material. Currently, infrared spectroscopy is the most accurate test for the detection of polymers in jadeite.
Type C jade has been artificially stained or dyed. The effects are somewhat uncontrollable and may result in a dull brown. In any case, translucency is usually lost.
B+C jade is a combination of B and C: it has been both impregnated and artificially stained.
Type D jade refers to a composite stone such as a doublet, a jade top with a plastic backing.
Dyed jade can be most easily distinguished from undyed jade by examination with a Chelsea filter; undyed jadeite will not show the red color of dyed jadeite or nephrite when looked at through the filter.
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