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
i n t o
t h e
s e a b e d.
Huge masses of jadeite are found in San Benito County,
California.
In Cloverdale, Sonoma County, California, jadeite veins
can be found.
WORLD JADEITE DEPOSITS
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.
Jadeite nodule
(height - 8.5 cm)
Guerrero Negro,
Baja California Norte,
Mexico.
Guatemala ‘s Jadeite
.
A unique jadeite, named "Galactic
Gold," naturally embedded with
various metallic inclusions
http://www.jades.centroamerica.com/whatisjade.htm
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]
and ferroactinolite [Ca2Fe5Si8O22(OH)2]. The magnesium in tremolite
is often partially replaced by iron and the two minerals grade optically
a n d c h e m i c a l l y o n e i n t o t h e o t h e r.
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
c
e
n
t
F
e203.
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
P e n i n s u l a r.
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
P
r
o
v
i
n
c
e.
http://www.gem.org.au/gallery/jadetext.html
South Austalia
Cowell
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
a l t e r a t i o n / r e t r o g r e s s i o n a s s e m b l a g e s.
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.
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 latestage 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
s e r p e n t i n i s e d u l t r a m a f i c r o c k s s u c h a s p e r i d o t i t e s.
Australian Nephrite
http://www.gca.com.au/GCA_australian.htm
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
http://www.gca.com.au/GCA_jadeart.htm
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
f
o
u
n
d.
Related Websites:
www.princessjade.com/
www.jademine.com/
www.canadianrockhound.com/
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
C a n a d a
i s
s o l d
t o
C h i n a.
PRINCES JADE MINE
http://www.princessjade.com/
One of the specially designed diamond impregnated saws for slabbing
jade at the Jade Queen Mine site on Mount Sydney Williams, B.C.
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.
This nephrite jade boulder, also known as the The Buddha Boulder, was
mined from Ogden Mountain and weighed 11,000 pounds.
KUTCHO CREEK
June 2000
Exploratory Diamond Drilling on new
Jade discoveries.
Drilling and removing jade found in place. Jade appears
(POLAR JADE MINE //AUGUST 2000)
"white" until cut open
A translucent slab of B.C. jade with its characteristic deep
green colour.
Preparing to transport jade to camp
Loaded and trimmed jade
ready for 100 mile trip to
highway over permafrost
trail. Each truck carries 13
t o n n e s o f j a d e.
OOOPS!! Halfway to
Highway! Same load
of jade, new 6 x 6
truck. Jade boulders
are buried underneath
i n a s w a m p.
http://www.jademine.com/
Jade
frog (height ~ 12cm)
by Gerd Dreher
from British Columbia
Canadian Museum of
Nature
(www.cst.cmich.edu/users/dietr1rv/
gemrxD-K.htm)
Jade tiles
used for
flooring,
fireplaces,
countertops,
tables and
lamps.
British Columbia jade and marble tiles
New Zealand, South Island
Nephrite
FineDeposits
green nephrite originally carved by natives into
religious
of objects and weapons
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
‘P
o
u
n
a
m
u’.
Pounamu is 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
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
r
i
v
e
r
s.
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.
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.
Jade Studio
http://www.mountainjade.co.nz/
ALASKAN JADE
Paul Howard
Elanora, 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
k n o w n
a s
A l a s k a n
j a d e.
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, streamrolled boulders such as the 10-pound example
f e a t u r e d
h e r e.
Wyoming, near Lander; since 1936
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
j a d e w i t h i n.
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
12t h c e n t u r y.
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).