References• http://www.cigem.ca/brazil/brazil.html• Dietmar Schwarz, 2 5 4 2 . เอกสาร

ประกอบการอบรมเชิ งปฏิ บ�ติ การเร��อง “ “มรกติ และพลอยติระก�ลคอร�นดั�ม . ภาควิ ชิา

ธรณี วิ ทยา มหาวิ ทยาล�ยเชิ ยงใหม$• 1996Delaney,J.V.Patrick, .G GG GGGGGG GG GGGGGG-G GGGGGG GGG G GGGGGGGGGGGGGG -GGGGGGG GGGGGG GG GGGGGG GGGGGG• 1987Fischer,M., . The emeralds of - theBelmontMi ne, Mi nas Ger ai s, Brazil. J.Gemm . -20, 446 456• Giuliani, G., and others, 1 9 9 0 .

Origin of emerald deposits of Brazil. -Mineralium Deposita 2 5 , 5 7 6 4

Emerald Deposits of Brazil

The search for emeralds in Brazil began about 500 years ago, after the arrival of the Portuguese in the country, however only in 1963 the first samples of the stone with real commercial value were found in the mine of Salininha, in Bahia, wiping out the old idea that Brazil had no precious stones.

History

• - 1617th centuries : in search of the legendar “Serra das Esmeraldas”

• beginning of 20th century : discovered some small deposits in Bahia state

• 1963 first important find of emeralds in Salininha mine, Bahia

• 1978 accidentally discovery of emerald deposit (Blemont Mine) in Minas Ge

r ai s• 1981 emerald mining (Blemont Mine) st ar t ed• 1981 discovery of Santa Terezinha

emerald deposits in Goias State• 1983 emerald mining started in

Socoto area, Bahia• 1988 discovery of Capoeirana

deposits near Belmont Mine• 1997 discovery of emeralds in theGG GGGG GGGGGG GG GGG GGGG GGGGGG G GGGG GGGGGG Tocantins State

BAHIA

MINAS GERAIS

GOIA`S

Emerald production in Brazil is concentrated in these three states

Geology

Basement of Archean Gneiss Complex (> 2.5 Ga.)

Overlies by - Proterozoic mafic ultramafic - and meta sedimentary/volcanic rocks

GGGGGGGGGGGGGG GG GG GGGGG G GGGGGGG• - Granitic Pegmatite Hydrothermal Type - I/A In mafic ultramafic rocks : Carnaiba- 20Socoto ( . Ga.), Belmont -Mine Capoei

rana (5 0 8 Ma.)• - Tectonic Hydrothermal Type - II/A In volcano sedimentary rocks : 520Santa Terezinha ( Ma.)

Brazilian Emeralds

• Major producers : Salininha and Carnaiba Districts, Bahia ; Sant

a Terezinha District, Goias; Nova Er a and Itabira Districts, Minas Gerias

. • Occurrences : alluvial,

hydrothermal and pegmatite deposits

• Chromophore GG V insome stones, not Cr asi n most ot her emer al ds.

• Br azi l i an emer al ds were once thought of as typically

- lighter toned and much yellow er compared to other sources. As for all generalities, there ar

e many exceptions; Santa Tere zinha has produced emeralds o

f exceptional color, though mo stly of small size.

Mining & Production

• Supervised by Federal Mining Department ( DNPM)

• Mining claim (5 years) = US$ 2mi l l i on• Mining cost per 1 kg rough = G GG 5000• 1m advance of shaft and tunnel

= - 600 1000

• Annual production = 50US$mi l l i on Santa Terezinha, Goia’s State = 6 0 % Carnaiba & Socoto, Bahia State = 3 0 % Itabira & Nova Era, Minas Gerais

State = 1 0 %

Goia’s: The "garimpo" is located in the municipality of Campos Verdes . Nowadays few c

ompanies explore there as the known mines are v ery deep (up to 600 meters deep), thus not permit ting their exploration by "garimpeiros"(garimpo w

orkers). The gems are of very small sizes but with good crystallization. At present the production is s

mall in volume and of lower commercial quality.Bahia: This "garimpo" presents a very irregular pr

oduction owing to its geological characteristics, bu t it provides with a reasonable quantity of rough m

aterial adequate for cutting, reaching competitive prices in the market. The production varies from lo

wer, commercial to extra goods in all sizes. At pres ent this "garimpo" is producing a reasonable amou

nt of rough and tending to increase production in t henear f ut ur e.

Minas Gerais: The production is concentrated in t wo places, one of them is Itabira , the only emeral

d mining activity enterprise in Brazil explored by ju st one company, a partner of CANELHAS that cons

- umes 7 0 8 0 % of the total production. Its prodGGGGGG GG GGGGG GGGGGG GGG GGGGGGGGGGG GG GGGGGGG GGG GGGGGGG . http://www.canelhas.com/brazilian_mines.htm

Nova Era, is a region close to Itabira. It is a more recent "garimpo" and its goods began to be accepted in the international market at the beginning of 1990. They are clearer crystals of bigger sizes with a bright shine. At present its production is small and irregular, what has reduced the market for this kind of product.

Nova Era Mine, Minas Gerais

MINING AT NOVO ERA AREA

The discovery of the mine of Salininha and the international acceptance of its gems changed the characteristics of the search for emeralds in Brazil, increasing the mining activity in the country, what brought about the discovery of new mines raising the country to one of the first positions in the world production of colored gems, besides being an important source of emeralds with very good quality.

Salininha Mine, Bahia

Salininha Mine, Bahia

Emerald Deposits of South Asia(Afghanistan, Pakistan and India)

Afghanistan1 : Panjshir Valley

India2 : Arawalli Mtn., Rajasthan

Pakistan3 : Swat Valley

Khaltar Valley (Khaltaro)

2

1 3

AFGHANISTAN

• Tectonic hydrothermal of type II/A2 (Hydrothermal veins cutting ophiolites)• Panjshir Valley 130 km N. of Kabul• discovered early 1970s• peak production of 1990s (US$ 10 mil. for rough)• source of revenue for Mujahideen !• difficult terrain, lacks of infrastucture• mining activities depend on political and military situations !Ref.• Emeralds of the Panjshir Valley, Afghanistan i

n GEMS & GEMOLOGY, Spring, 1 9 9 1• -://. .//.

Panjshir Valley, Afghanistan with the background of Hindugush Mtn.

Arial view of Panjshir Valley

Village of Khenj in Panjshir Valley. The

village is like a boom town where emerald mi ners buy their supplies and food on the way t

o the emerald mines in the mountains.

Emerald miners a t Khenj standing

in front of a covered generato

r left by the Russi an army. The min ers were able to g

et this generator into operating co

ndition for use in their mining oper

ation.

Emerald miners s howing off their

new Swiss drill at an emerald mine

located above th e Village of Meki

ni, Panjshir Valle y, Afghanistan.

Emerald miners s tanding in front

of their tunnel in Panjshir Valley, A

fghanistan. The o penings of most s

hafts are three to four feet high an

d approximately three feet wide.

Green emerald crystals on the roof of an emerald tunnel.

A 43.47 carats Panjshir emerld crystal

PAKISTAN

Swat Valley : Type II/A2 (Hydrothermal veins cutting Mingora ophiolites melange)• Mingora deposits• Makhad deposits• Guajar Kili depositsKhaltaro : Type I/A (Pegmatite culling mafic-ultramafic rocks)• Khaltar Valley• deposits near Khaltaro village

Kazni,A.H. and Snee,L.W., 1 9 8 9 . Emeralds of Pakistan . Elite Publishers Ltd.

Paki st an

MINGORA (Swat Valley)

• found in 1958 near Mingora City, Swat District• fine emeralds comparable to Muzo’s• known as “Pakistan or Swat Emeralds”• Mining done by GEMCP (Gemstone Corp. of Pakistan).• Mineralization in shear planes, fractures, stockworks and tension gashes. • 15-30 cm emerald-bearing zone around quartz lenses• Commonly up to 30 carats crystals of good green colour and clarity.

MAKHAD (Swat Valley)

• near Makhad Village, 19 Km NE of Mingora• intermittenly mined (Local and GEMCP)• Emerald crystals (10 carats or greater) in talc-carbonate schist host rocks• very dark green, opaque to translucent, full of inclusions (talc, carbonate minerals etc.).• low gemmological value.• now abandoned

GUJAR KILI (Swat Valley)

• 24 Km ENE of Mingora• discovered in 1981 by GEMCP• 3 acres outcrop of Mingora ophiolite melange• faulted and fractured talc-carbonate host rocks• limonitization is the dominant wall-rock alteration• emeralds in limonitzed fault and joint planes• large crystals are 100-200 carats weight• deep blue green, transp.-transl., few inclusions• since 1982 annual production > 10,000 carats

KHALTARO

• the deposit is at 4,500 m MSL, rugged terrain• emeralds in peg. intruded mafic-ultramafic rks.• 3 months mining periods (July-September)• mostly 1-3 cm. euhedral crystals• inclusions and cracks are common• known production only 600 carats by GEMCP

INDIA

• Type I/A (Pegmatite culling mafic-ultramafic rocks)• Inclusions reflect mineralogy of host rock e.g. talc, Cr-mica (fuchsite), biotite, apatite etc.• Comma shaped fluid inclusion (similar to those from Santa Terrezinha, Brazil)

• Mined since 1955 at Arawalli Mountain, Rajasthan • 200 km belt of Precambrian schists intersected by altered peridotite bodies, pegmatites and granites.

Emerald Deposits of Europe

AUSTRIA

• Habachtal deposit mined during Roman Empire

RUSSIA• Takovaya-Malysheva deposits

NORWAY• Eidsvoll depositsNORWAY

EkaterinburgTakovaya-Malysheva

Eidsvoll

Habachtal

RUSSIA

• deposits in Ural area, 90 Km NE of Ekaterinburg

• discovered by Maxim Kojevenikov near Takovaya river in

1830 (mine opened in 1831)

• during WW II was the main source for Be

• 3-4 mil. carats of emerald and green beryl per year in 1950s

• underground mining at Takovaya-Malysheva since 1970s

• non-profitable mining and marketting problems by ends of

1990s

Australia has been a fairly important producer of emeralds. Several important sites in New South Wales and Western Australia have been described. Many of the emeralds that have been shown in colored prints are probably closer to green beryl but some fine blue green stones are known.

Emerald Deposits of Australia

• Poona deposits• - Emmaville Torrington deposits

Emerald Deposits of Africa

Colored gemstone mining in Africa is very different however. The vast majority of the colored gemstone production is produced by small scale miners often using only picks, chisels, hammers and shovels. Many of these small scale miners are "illegal" (unlicensed) and often mine until their food runs out or the mining becomes too difficult.

NG

EG

SA

MZ

SM

M

TZ

ZA

ZB

Ndola Rural emerald deposit , 200 Km north ofGGGGGG

(S.G.=2 .7 5 ; R.I.E=1 . 583, R.I.O =1 .5 9 0 )

• Once a major producer; 40% of all emeralds

1989sold in U.S. in wGGGG GGGG GGGG GGGGGG. • In schists adjacent to

pegmatites; can contain t ourmaline and biotite incl

usions.

Lusaka

• Excellent clarity, but often darker, with a more noticeably bluish cast than Colombian emerald.

ZAMBIA

Zambian emeralds, tho ugh not as prevalent in the market as those fro

m Colombia or Brazil, ar e easy to love and wort h seeking out for their d

eep tones, clarity and g enerally lower prices. A

source in Zambia says t he domestic emerald in

dustry is healthy, with s ome big operators such

as the Kamakanga Mine and Kagem . A majority

of emeralds still exit the country illegally, though

the Ministry of Mines re ported production figur

es of 588 kg of emerald in 1996, up 350% from

1995.

Kamakanga Emerald Area, Ndola Rural, Zambia

August 1984

GGG GG GGGGG GGGGGGGGG GGGG GG GGG GGGG G GGG GG , the exploration and mining is done by t unnel i ng

under gr ound . The miners and I are looking for a roGG GGGG GGGGG GG - mica chlorite schist in contact with

a pegmatite which is were emerald mineralizationoccur s . Although many miners are injured and ev

en die working under these conditions, malaria in t he bush areas was a much greater health risk and

claimsmany l i ves.

Sandawana Valley Deposits

• S.G.=2.755; R.I.E=1.586, R.I.O=1.593

• Mostly small stones (0.5 carat or smaller), heavily flawed in

larger sizes

• Excellent colour

• In schists invaded by pegmatites and quartz veins

• Noted for inclusions of acicular tremolite, and for

somewhat higher R.I. than Colombian and Brazilian emeralds.

ZimbabweSalisbury

Emerald Deposits of North America

Hidden, North Carolina

In the United States, few emeralds have been found and most have bee

n recovered from near Hidden, Nort h Carolina . A very large emerald that

became the subject of a bitter law su it was mined there in the 1 9 8 0 '

s. The t r agi comi c out come was t hat one of t he mi ner s i nvol ved sawed t he ver y fi ne 14 inch crystal (valuedatseveralmillionsof

dollars) in half and destroyed much of the value of this essentially pricel

ess item. Except for the North Caroli na finds, no other state has had any

significant emerald production.http://www.gemkey.com/newscenter/news/

7 966default.asp?NTYPEID= &NNEWSID=

USA

G GGG GGG GGGG GGG dred years, the

Hiddenite area saw "emerald rushes" c

ome in go, with sig nificant specimens

G G1 9

0 6 , 1 9 6 9 , 1971 1and

980 199. In 5 , fresh off the dis

-covery of a 20.20 c - aratgemqual i t y emerald, Hill set up North A

merican EmeraldG GGGG GG GGGGGGGGGG GGG G GGG GGG GGGG Mine , which produ

ced over 3 ,5 0 0 carats of emera

ld rough during itsGGGGGG GG GGG GGGGG

'8 0 s, as well as p reviously unexplor

GGGGGG.

GGG GG GGGG G GGG GGG GGGGGGG GGGG G GGG GGG GGGGGG GG GGGGG GGGG GG

Hiddenite, North Carol.

Aquamarine Deposits

Africa : Madagascar, Namibia, Nigeria, Zambia, Zimbabwe America : Brazil, USA

Europe : Russia, N. Ireland Asia : Afghanistan, India,

GGG GGG GG,

AQUAMARINE DEPOSITS

Aquamarine

Birthstone for the month of March. Name is applied to blue to greenish-blue to bluish-green ("sea green") beryl.

Most common untreated material is greenish-blue, although very light to medium blue varieties are by no means rare. Found exclusively in pegmatites, or as water worn, frosted pebbles or cobbles in stream gravels. known.

Africa : Madag ascar,Namibia,

Nigeria, ,

Zimbabwe America : Brazi

l, USA Europe : Russi

a, N. Ireland Asia : Afghanis tan, India, Paki stan, Sri Lamk

G

Most important source, mostly from the state of Minas Gerais, near the town of Teofilo Otoni. Famous but now depleted deposit of Santa Maria noted for exceptional deep "electric" blue aqua.

• Common lighter blue aqua shows deepest color only in stones of 5-10 cts. or more.

•Blue-green stones sometimes referred to "Brazilian Aqua."

BRAZIL

Ground-piercing radar to prospect for gemstone deposits in Brazil

Prospectors have utilized a whole range of methods to locate precious gems. Some of these methods are scientific, some pseudo-scientific, some employ common sense and others are just plain bizarre.

AfricaMadagascar - usually m

edium dark blue. Darke r aqua. sometimes refe

rred to as " MadagascarAqua ."

Africa G GGGGG(, a, Zambia, Zimbabwe)

- 198mostly since 2 . ,Noted for untreated

deeper blue color that persists in even the sm

- 12allest cut stones. carat gems retain a "sp

ectacular" deep blue. Most Nigerian stones s

how a slight green overGGGG GGGG GGGGGG GG GG

moved by heat treatmeGG (Cr is chromophore,GGGGGG GGGG GG GGGGGGG G

n treated Brazilian aqu.).

Kapilinkesa Aquamarine Mine, Lukusuzi National Park,

As the mine was located in a national park, no mechanized operations were allowed. All mining was done by hand and by utilizing large fires. As in the picture, these large fires were used to break the large quartz pegmatite. The fires were set in the late afternoon and were allowed to burn throughout the night. The heat would crack the rocks and allow for easier breaking by sledgehammers. The mining here is an example of how a typical small scale mine operates although the utilization of fire was very innovative.

ZAMBIA

Mining in remote areas is very difficult. As we were 120 miles from the nearest town on very bad bush roads, being self sufficient in our operation was essential. In this picture, we are sharpening steel chisels after first softening them in a homemade kiln and then pounding them to a sharp point. This was a constant chore and one that all small scale miners used.

Kapilinkesa Mine, Lukusuzi National Park, Zambia

Kapilinkesa Mine, Lukusuzi National Park, Zambia

The production of aquamar i ne raw crystals just af ter they are pulled from the ground. From this sta ge the crystals are broken up and chipped clean

with tungsten pliers to expose the "clean" gemm y areas. This is a very tedious and long process a s it must be done very carefully to preserve as m

uch of the gem areas as possible. Only a small pe rcentage of the crystals actually yielded clean ge

GGGGGGG.

Kapilinkesa Mine, Lukusuzi National Park, Zambia

A crystal fragment of top quality aquamarine only minutes after it was mined. After separating, it yielded a 5 gram absolute gem piece! It is moments like this that all gemstone miners wait for.

This is very fine material, after 2 months production, and it was all sold immediately to a well known Brazilian dealer who then called it of Brazilian origin after cutting and polishing. Most of the production, as in all gemstone mines is in the smaller sizes.

A 169 carat aquama rine from Nuristan,

Afghanistan faceted by Allen Pobanz.

Valued at $85,000.

AFGHANISTAN

Aset of aquamari ne crystals from Nu

ristan, Afghanistan

Beautiful 2 1/2 i nch high

Aquamarine cry stals in mica fro

m Nuristan, Afg hanistan. Price

d at $180.00.

Gems from Pech Nuristan

Nuristanis with Gems

END OF BERYL SHOW

A STATUS REPORT ON GEMSTONESFROM AFGHANISTAN

By Gary W. Bowersox

© 1 9 8 6 Gemological Institute of America First published in GEMS & GEMOLOGY, Winter, 1985

-http://gems afghan.com/articles/status.htm

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