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California Jade Deposits

California Jade Deposits.

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California Jade Deposits

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  1. California Jade Deposits The region within the Monterey Marine Sanctuary known as the Jade Cove area consists of a series of small coves located south of Big Sur, near Gorda, California. Jade occurs in veins in the serpentine bedrock formation, extending from inland mountains, down the cliffs and into the seabed. Huge masses of jadeite are found in San Benito County, California. In Cloverdale, Sonoma County, California, jadeite veins can be found.

  2. WORLD JADEITE DEPOSITS

  3. Jade in the New World was used extensively by the Maya, Aztec, Olmec and other pre-Colombian cultures. It was considered to have magical properties and was the most precious object on earth, reserved for the use of the noble class. The conquistadors were amazed at the devotion the natives of the New World showed for this "green stone" which they prized more highly than gold. Due to its permanent, unchanging eternal properties it was considered a passport to immortality.

  4. Jadeite nodule(height - 8.5 cm) Guerrero Negro, Baja California Norte, Mexico.

  5. Guatemala ‘s Jadeite A unique jadeite, named "Galactic Gold," naturally embedded with various metallic inclusions http://www.jades.centroamerica.com/whatisjade.htm .

  6. Nephrite Nephrite (chen yu or true jade), the traditional Chinese jade, is mineralogically a monoclinic amphibole of variable chemistry that ranges between the end members tremolite [Ca2Mg5Si8O22(OH)2] andferroactinolite [Ca2Fe5Si8O22(OH)2]. The magnesium in tremolite is often partially replaced by iron and the two minerals grade optically and chemically one into the other. The colour of nephrite varies from white, yellow, green and brown to black, depending on the amount of iron substituting for magnesium. Iron-poor tremolite is white, grey or green; whereas iron-rich varieties (actinolite) are darker green, grey-green, and grading though to black. Cowell jade is nephrite jade that has an iron content of up to 7.9 per cent Fe203.

  7. NEPHRITE DEPOSITS OF AUSTRALIA Presently, the largest known deposit of high-quality (nephrite) jade in the world is located outside of the small town of Cowell, on South Australia’s Eyre Peninsular. Ninety-one (91) separate jade outcrops were identified in 1974, but subsequent mapping has now increased this to well over a hundred. All outcrops of nephrite are located within an area of about 10 km2, referred to as the Cowell Jade Province. South Austalia Cowell http://www.gem.org.au/gallery/jadetext.html

  8. GEOLOGY The (nephrite) jade bodies at Cowell typically have elongate, lensoid shapes in outcrop. Host rocks for Cowell nephrite are dolomitic marble and banded calc-silicate of the Early to Middle Proterozoic Minbrie Gneiss Complex. These high-grade metamorphic rocks were produced during the first and second deformational events of the Kimban Orogeny, about 1840 and 1780 million years (Ma) ago respectively. Subsequent retrogression occurred about 1700 Ma with later cross-warping and alteration about 1590-1600 Ma. Nephrite only formed within the alteration/retrogression assemblages.

  9. Alteration zones, consisting of tremolite, chlorite, epidote, clinozoisite/zoisite and talc, occur particularly along the margins of, or in close proximity to intrusive chloritised feldspar rock that has intruded dolomitic marble.

  10. Cowell nephrite formed: 1. Within alteration zones as large lenses up to 40 m long by 3 m wide, conformable with lithological layering. 2. Within cross fractures up to a metre wide parallel to the axial plane of late-stage cross-warping. Nephrite in cross fractures is typically high quality, fine grained, massive, and dark green to black - but sometimes it does occur in rarer translucent light green colours. 3.By irregular alteration of coarse grained, brecciated diopside? producing schistose nephrite that often has diopside inclusions. The Cowell geological setting of Middle Proterozoic dolomitic marble host rocks contrasts with other major occurrences of nephrite in New Zealand, Canada and Taiwan; where nephrite lenses occur within or along the faulted margins of serpentinised ultramafic rocks such as peridotites.

  11. Australian Nephrite http://www.gca.com.au/GCA_australian.htm

  12. Carvings made from Cowell (nephrite) jade Harp made from carved black Cowell (nephrite) jade and cast silver http://www.gem.org.au/gallery/index.html

  13. http://www.gca.com.au/GCA_jadeart.htm

  14. Southern Frazier River drainage, British Columbia Fine nephrite, supports large industry Some nephrite found in place with serpentinite. A recent find in British Columbia brings an entirely new nephrite jade to market. It is called "Polar Jade," because of its origin and is the greenest and hardest nephrite yet found. Related Websites: www.princessjade.com/ www.jademine.com/ www.canadianrockhound.com/

  15. The Jade Mines of B.C. http://www.canadianrockhound.com/2000/02/cr0004202_jademines.html Canada has been selling jade all over the world for many years. We have sold jade to New Zealand for the Maori to carve since 1974 when Joe Bell and Jeannie MacCulloch went there on a marketing trip. Canada is also selling jade to Wyoming and in 1988, 700 tonnes of Canadian nephrite jade from British Columbia was sold to China – 300 tonnes of this was Jade West production. Ninety per cent of the jade produced in Canada is sold to China.

  16. PRINCES JADE MINE http://www.princessjade.com/

  17. One of the specially designed diamond impregnated saws for slabbing jade at the Jade Queen Mine site on Mount Sydney Williams, B.C.

  18. M.J. Beley shows a large slab cut from a boulder at The Jade Queen Mine on O'Ne-ell Creek, Mount Sydney Williams, B.C.

  19. This nephrite jade boulder, also known as the The Buddha Boulder, was mined from Ogden Mountain and weighed 11,000 pounds.

  20. KUTCHO CREEK June 2000 Exploratory Diamond Drilling on new Jade discoveries.

  21. Drilling and removing jade found in place. Jade appears "white" until cut open (POLAR JADE MINE //AUGUST 2000)

  22. A translucent slab of B.C. jade with its characteristic deep green colour.

  23. Preparing to transport jade to camp

  24. Loaded and trimmed jade ready for 100 mile trip to highway over permafrost trail. Each truck carries 13 tonnes of jade. OOOPS!! Halfway to Highway! Same load of jade, new 6 x 6 truck. Jade boulders are buried underneath in a swamp.

  25. http://www.jademine.com/

  26. Jade frog (height ~ 12cm) by Gerd Dreher from British Columbia Canadian Museum of Nature (www.cst.cmich.edu/users/dietr1rv/ gemrxD-K.htm)

  27. Jade tiles used for flooring, fireplaces, countertops, tables and lamps.

  28. British Columbia jade and marble tiles

  29. New Zealand, South Island Fine green nephrite originally carved by natives into religious objects and weapons Nephrite Deposits of

  30. POUNAMU(GREENSTONE) & (NEPHRITE JADE) http://www.kahu-artistry.com/pounamu.html The scientific name is nephrite jade, commonly known as Greenstone in New Zealand, but its native name given by the Maori people is ‘Pounamu’. Pounamuis found only on the South Islands Westcoast within New Zealand, in two main areas - Hokitika (the Pounamu Jade Capital) in North Westland and in the inaccessible bush below Jacksons Bay - South Westland. http://www.lawas.co.nz/LINKS/tikipage.htm

  31. Pounamu is found in river beds of New Zealand's Westland district. The largest fields being found at Arahura & Taramakau.. No rock seam of nephrite has been found. Over time boulders revealed by earth movement & alluvial erosion are flushed out into the rivers. The emerald green of kahurangi & the milkey green of inanga are among the varieties most dear to the Maori. The Maori regarded Pounamu as a treasure of immense spiritual & material value. Its ethereal qualities making it the most prized possession representative of mana (spiritual power) & rank. The courage, endurance & skill involved in locating & working the stone added to its prestige. For its beauty & strength, the Maori used jade in place of metal for jewellery, tools, and weapons.

  32. This traditional triple crossover pendant design in South island nephrite jade is by master carver Colin Bennett. New Zealand jade or 'pounamu' is among the finest and most beautiful in the world. To wear a piece like this conveys to the world that you are a person of much 'mana' or prestige.

  33. Jade Studio http://www.mountainjade.co.nz/

  34. ALASKAN JADE Paul HowardElanora, Queensland The Australian Gemmologist, V. 20, No. 4, October - December 1998 Gem quality nephrite known commercially as Alaskan jade is mined from several deposits in north west Alaska's Baird or Jade Mountains. First discovered by native Eskimos, this attractively coloured and patterned nephrite is considered to be a jade of world significance In this paper, the author will summarise present knowledge concerning the history of exploitation, occurrence, economic deposits, methods of recovery, gemmological features, and present status of supply of the nephrite known as Alaskan jade.

  35. Alaskan Nephrite Jade Shown is a nephrite jade boulder and necklace, from the Kobuk River region, northwestern Alaska. Artifacts made from Kobuk River nephrite are hundreds of years old and have been found at archaeological sites along the Bering and Pacific coasts of Alaska and British Columbia, and the Arctic coast of Canada. Government geologists determined that the jade and asbestos at the locality occur in a 40-mile stretch of altered ultra basic rocks consisting mainly of serpentine that extends north of, and roughly parallel to, the Kobuk River. The finest material is usually found in smooth, stream-rolled boulders such as the 10-pound example featured here.

  36. Nephrite boulders, some very large (house-size), in glacial deposits that cover the chaparral and desert country around Lander. Some lovely green jade; also "golden jade", a golden brown variety. Most boulders are covered with a white to gray weathering rind that hides the true color of the jade within. Wyoming, near Lander; since 1936

  37. Turkestan (central Asia between Iran and Siberia) Earliest known source of nephrite Used by early Chinese for carving Nephritic jade was originally found in the form of pebbles from alluvial deposits in Chinese Turkestan (Xinjiang) and was first mined from rock in the 12th century.

  38. Others: Poland (white nephrite); The Jordensmishl Nephrite Jade Deposit in Poland (Discovered by Herman Traube 1885) Taiwan; Japan; U.S.S.R. (near Lake Baikal, green nephrite).

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