Emerald The Most Valuable Beryl; the Most Precious Gemstone ------extraLapis English No.2 ------
with Contributions by Christa Behmenburg, Lawrence Conklin, Gaston Giuliani, Maximilian Glas, Patricia & Michael Gray, Gunter Grundrnann, Rupert Hochleitner, Jan Kanis, Lore Kiefert, Karl Schrnetzer, Dietmar Schwarz, Zak Swartz, Marc Wilson, Michael Wise and Marisa Zachovay Translation by Alfredo Petrov and Gunther Neumeier Photos and Diagrams by Roberto Appiani, Marcus Budil, Helmut Burger, Warren Dobson, Gilson Archive, Gaston Giuliani, Maximilian Glas, Konrad Gotz, Gunter Grundmann, Henry Hanni, Tino Harnrnid, Rupert Hochleitner, Jan Kanis, Fotodesign Lichtblick, Hwa Ja Nier, Fotostudio Otto, Eckehard Petsch, Harold & Erica van Pelt, Federico Pezzotta, Jeff Scovil, Karl Schmetzer, Dietmar Schwarz, John Sinkankas, Franco Valoti, Stefan Weiss and Debra Wilson
Valued Since Prehistoric Times as the Most Precious of Gemstones: Emerald Whether from ancient India, Greece, Rome or Colombia, emeralds have alwavs been a highly prized gemstone, This postcard depicts pre-Columbian emeralds from the Calima culture circa 1,000 to 1,500 AD. The largest stone weighs 37 carats. Stones from the Ronald Ringsrud collection, Saratoga, California; photo Tino Hammid
IN COLLABORATION WITH LAPIS MAGAZINE, CHRISTIAN WEISE VERLAG, GERMANY AND LAPIS INTERNATIONAL, USA
The Origin of Emerald...
by As a beryl, emerald is composed primarily of the While aquamarine and other pegmatite minerals Dietmar Schwarz, abundant elements silicon, aluminum and oxy develop in relatively calm environments which Gaston Giuliani, gen. The fourth primary component, beryllium, allow for continuous crystal growth without Gunter is rare in the Earth's upper crust (1.5 ppm); thus, strong perturbations, emeralds are formed in Grundmann beryl is not a common mineral. Beryllium, as a geologic environments characterized by abrupt and rule, comes from rocks of the continental crust. changes and mechanical stress. Maximilian Glas Its sources include pegmatites, aluminum and sil Smaller crystals with considerable internal de icon-rich magmas, clayston~s and black shales fects such as fissures, fractures or foreign solid with their metamorphic equivalents, such as or inclusions are consequences of forming in a per thogneisses and mica schists. turbed mineralogical-geologic environment, and The elements that give emerald its color, chromi partially healed or unhealed fissures and fractures um and vanadium, are less rare than beryllium in are quite common. Understandably, the presence the Earth's upper crust (185 and 230 ppm respec of such defects lower a crystal's mechanical resis tively). They are concentrated in dunites, tance. Unable to withstand the stress of river peridotites and basalts of the oceanic crust and transport, emerald is rarely found in secondary Earth's upper mantle. Concentrations of chromi deposits. um and vanadium sufficient to form emerald can also occur in sedimentary rocks, particularly black shales. Ages of Emerald Mineralizations With beryllium concentrated in the Earth's Emerald deposits are known from five continents, continental crust and chromium and vanadium with South America having been by far the most concentrated below in the upper mantle, unusual important emerald producer for many years. geologic and geochemical conditions are required Emeralds formed during almost every geologic for chromium and/or vanadium to encounter epoch. The most intense emerald formation beryllium. Though there are a few deposits in occurred during continental collisions, which which the circulation processes inside one geo gave rise to large mountain complexes, extended logical unit are sufficient for emerald formation fault zones, regional metamorphic overprints and (e.g., the black shales of Colombia), but in gener eventually to further uplift and erosion. All of al the source rocks must first be brought together these events favor the formation of emerald de and then channels must be opened to permit the posits. Emerald can, therefore, take its place circulation of fluids and the mobilization of among the oldest gemstones in the Earth's crust: elements. • 2.97 billion years: the Gravelotte emerald deposits of Transvaal in the Archean of South Formation of the Deposits Africa formed. Disparate bodies can be brought together through • 2.6 billion years: the emerald deposits in the actions of plate tectonics. The resulting folds Poona, Australia and Sandawana, Zimbabwe and faults mobilize fluids that move along the formed during the last rock forming processes. newly created fractures. As they move, these flu • 2 billion years: the Brazilian emeralds of ids can then dissolve and transport the Camafba and Socot6 in the state of Bahia elements necessary for emerald formation. formed during the early Proterozoic. Once the necessary elements have been brought • 500 million years: the Brazilian deposits in Mi together, emeralds can crystallize in diverse geo nas Gerais (Belmont Mine, Capoeirana, Piteiras) logic environments: as a rock-forming mineral in and the enormous deposit of Santa Terezinha in schists and gneisses or as isolated crystal pockets Goias both formed in the Paleozoic (510 and in geologic structures such as veins along fracture 520 million years ago respectively). In Africa, zones, faults, breccias, lenticular vugs, druses, the emerald occurrences of Mananjari and miarolitic cavities or quartz lenses. Ianapera formed 490 million years ago.
18
siderite-caIci te-quartz rocks: counrry ASIA rock is carbonate-bearing metapelite Emeralds and graphite schist Sim: Gujarkili, Chabargh, Makhad, PAKISTAN • Mohmand Region 2 Alpurai, Malam, Bar Kotkai, 3azarkot. of the Gandao 100 workings in a 1 km area also Khazana (Sharnozai Region) on the NW slopes of Tora-Tigga Mt. discovered early 1990's SE of Tora-Tigga viIlage. Mohmand Incl: Actinolite, Fuchsite, chrornite, Region. 43 krn NW of Peshawar, NW chromium-dravite. enstatite, plagioclase, World Pakistan tourmaline, gersdorffite. magnesite, Notes on known emerald occurrences Finds: No commercial significance dolomite, pyrrhotite, chlorite and quartz by Giinter Grundmann from the Beryl: Green beryl, colored (at least in Ref: Arifet al (J996) Technische Universitat, Miinchen. Gandao) by vanadium (up to 0.7%) and Gaston Giuliani and chromium (up toO.l%) PAKISTAN • Bajaur Region from the Institut de Recherche pour Geo: Countless quartz veins and lens Barang-Turghao (Mor-Darra) 80 km Ie Developpement et CRPG/CNRS, es in an alternating greenschist Nancy dolomite layers with mobilization of N of Peshawar In the Bajaur region beryllium from nearby beryl-bearing Finds: No commercial significance Abbreviations: pegmatites Beryl: Colored by chromium and iron Geo: Contact metasomatism between Sim: Similar or other deposits Mat: Quartz veins and lenses In dolomite rock ultrabasic and quartz-feldspar rocks Finds: Quality of emerald Sim: Nawe Kill (Nawe Dand), Mat: Quartz-calcite-feldspar veins in specimens and significant Finds Tsapari, Bucha, Pranghar, Khanori Kot talc schist at contact with amphibole Beryl: Type ot beryl or emerald and and Zankhae chlorite-talc schist and talc-carbonate the chromophorous elements lncl: Quartz, dolomite, rrernolite, talc, rocks (as weight % of the oxides Cr20:;, chlorite, epidote and phlogopite Sim: Arnankor. Maimoln. Nawe Dand: V20:; and FeO) Ref: For Pakistan, AFghanistan and south of Nawe Dand village, 40 krn N Geo: Geology and origin India: Kazrni and Snee (1989) of Peshawar, Bajaur region Mat: Matrix or host rock Incl: Quartz, plagioclase, calcite, Incl: Solid inclusions (fluid inclusions PAKISTAN • Swat District phlogopite. talc, chlorite, actinolite are not noted) Mingora Mine. in the Swat River Val Ref: References or recommended ley, 200 km NE of Peshawar. Largest PAKISTAN • Gilgit Division reading for further information deposit in Pakistan: discovered in Khaltaro deposits: known as Ravjud on a deposit 1958. Five mines, Mine I (Farooq near Khalraro, Haramosh Range, Mine). Mine 2. Mine ], lslarnia 70 km E of Gilgit, northern Pakistan: Trench, Carrel's Trench. spreading discovered 1985, rugged terrain at SSW to NNE over I km 4, I00 m in the Nanga Parbat Finds: Richest deposit in Pakistan Haramosh massif with the best quality finds. Emeralds Finds: Inclusion-rich and Fractured easily detach From matrix: matrix emeralds, rarely gem quality: rough specimens rare: crystals I to 2 em, stones I to 3 cm diameter rarely up to 10 em Beryl: Colored pale to medium green Beryl: Colored by chromium and iron: by chromium and iron color always inhomogeneous, often Geo: The only deposit in Pakistan sharply zoned; high magnesium with contact metasomatism between contents (up to 3ophiolite zone; Mat: Medium- to coarse-grained beryllium introduced by hydrothermal biotite-muscovite-aIbite-quartz fluids of magmatic or regional meta tourmaline-Fluorite zones in miarolitic morphic origin pegmatite Mat: Magnesite-talc-quam schist. Incl: Quartz. biotite, white mica, talc-chlorite-dolomite schist and chlo plagioclase, tourmaline, fluorite rite schist, quartz lenses, magnesite- Ref: Lams et al (1996)
24 The World of Emeralds in 2002
AFGHANISTAN • Konar Province known already in Pliny's time as the quartz and carbonate Badel Mine near Badel, Konar Province, smaragdus from Bactria (presentday Ref: Bowersox et al (1991); Sabot et al NE Afghanistan Iran and Afghanistan); the deposits (2000); Vapnik & Moroz (200I) Finds: Crystals inclusion-rich, frac stretch NE-SW from Aryu, past Deste tured; gem quality rare Rewat and Mikeni, as far as Khenj, over N. INDIA • Bubani, Rajhastan Beryl: Grass green, often milky clouded an area of 400 krrr', elevation 2,100 to Bubani Mine in the Rajhastan emerald Ceo: 20 m long, 20-50 cm wide 4.300 rn: Khenj in the Kapisa district, belt (stretches over 200 krn SW-NE pegmatite dikes in arnphibolites with Parwan Province, 110 km from Kabul between the cities of Ajrner and metasomatic contactzones of phlogopite Finds: The best material came from the Udaipur in Rajhastan Province) schist Mikeni and Khenj mines; crystals to Finds: First finds in modern times, Mat: Phlogopite schist 5 ct, gem quality over 10 ct rare, but 1943; overwhelmingly low to medium Incl: Phlogopite, quartz, feldspar exceptionally to 15 ct quality stones with good color, purity Ref: Rossovskiy (1980) Beryl: Saturated green color from chromium rare; the best Indian emeralds are from the Rajghar deposit AFGHANISTAN· Laglunan Province Ceo: Regional metamorphic-metaso Lamorida and Korgun Mines, Lagh matic; beryllium-rich hydrothermal flu Beryl: Pale green to deep green porphy man Province, NE Afghanistan ids reacted with muscovite schists roblasts colored by chromium Finds: Small quantities: gem quality Mat: Alternating metasediments and Ceo: The series (phyllites) of the Delhi rare meta-gabbros in an upper greenschist System is cut by numerous tourmaline Beryl: Moderate green, cracked or facies cut by quartz-ankerite veins or granites and pegrnatites; emerald-bear lightly included silicified zones of phlogopite, albite, ing veins are at the metasomatic contact Geo: Probably pegmatite dikes tourmaline and pyrite between the pegmatites and talc schist Lit: Laurs (2001) Sim: Sahpetaw, Burak, Abal,Takatsang, Mat: Phlogopite schist, actinolite Sakhulo. Pghanda, Qalat, Zarakhel, schist, talc schist and quartz-feldspar AFGHANISTAN • Panjshir Valley Derik, Buzmal, Yakhnaw, Shoboki, muscovire-rourrnal ine rocks Buzrnal, Khenj and Mikeni Mines in the Darun Rewat (incl. Riwat, Dahane Sim: First production area: Ajmer-Mer Panjshir Valley, Parwan province; de Revar) and Puzughur wara with Chat, Rajghar and Bithur; posits SE of the PanjshirRiver perhaps Incl: Albite, phlogopite, goethite, pyrite, second area: Mewar with Tekhi (Tikki),
25
South America: Colombia The Western and the Eastern Emerald Zones of the Eastern Cordillera: Still Number 1 in the World
Dieunar Schwarz South America is the world's most emerald-rich largest deposits in Colombian emerald history. and continent. Colombia alone produces about 60 The emeralds of the Eastern Cordillera are ex Gaston Giuliani percent of the emeralds on the world market while tremely difficult to mine, and are found in narrow report all the most Brazil's 1999 production was worth some 50 mil veins and breccias in zones where tectonic de important lion US dollars. While there have always been formation occurred. These zones can rarely be emerald deposits rumors about new emerald finds in Peru, Mexico, followed over any distance, and there are pro the world Bolivia or Ecuador, it the quantity and quality of nounced variations in emerald concentration and the emeralds of Colombia and Brazil that make quality throughout the deposits; furthermore, South America the world emerald leader. many veins In emerald-bearing areas do not
Age-Old Adornment
37.08 CI pre Columbian emerald head. Ronald Ringsrud collection; Jeff Scovil photo Right: A trans parent crystal (2.2 cm high) and a cut stone (1.66 ct.}. Co lombian eme- ralds are among the most beauti ful on earth. Harold & Erica van Pelt photo
Colombia: Nearly 200 Localities! There are nearly 200 known emerald localities between 4-6° north and 73-74° west in the Eastern Cord iJ lera. The emerald districts stretch NNE to SSW across two zones of mineralization: • The western zone or Vasquez-Yacopf mining district encompasses the Yacopi (La Glorieta), Muzo, Maripi (LCI Pita, Polveros), Coscuez and Perras Blancas deposits: contain emeralds. It is often impossible for • The eastern zone or Cuavio-Cuateque mining geologists, even after many years of research, to district includes the Chivor (formerly Somon accurately predict the spatial expanse and doco), Gachala and Macanal deposi ts. profitability of these vein systems: thus mining The locals knew of practically all of the deposits can be performed in one of two ways: before the 16th century Spanish conquest. Two • Following the emerald-bearing joints literally recently developed mining areas, La Pita and centimeter by centimeter; Polveros, lie between the Muzo and Coscuez • Mining the entire emerald-bearing rock units; Mines in the Maripi mining district along the Rio thus processing large rock masses. Minero, La Pita is thought to be one of the Pre-Columbian miners dug shafts and tunnels try- ing to follow the emerald-bearing veins, and this in 1559/60, founded the town of Santfsima has remained the major mining method in the Trinidad de los Muzos and focused on their Eastern Cordillera for many centuries. quest for emeralds. Local Indians led the way to the tap-y- acar , or A Difficult Road for the Conquerors green stones , and in ]564 following numero us Long before the Spanish conquistadors arrived in insignificant finds, the Spanish located the major the 161h century, the native peoples mined emer deposits. Three years later, a mining company alds. This gemstone was held in high esteem in was founded to mine Somondoco. The native s the new world much as it was in the old. Colom were forced laborers, and hostilities with the bian emera lds were traded to the Mayas, Incas Indians as well as a labor shortage led to a and Aztecs who used them for jewe lry and ritual. temporary mine closure toward the end of the ' h In the middle of the 16' h cent ury, the Spanish 16 century. began to force their way into the mines of the The Spa nish thirst for emerald s and wealth was Eastern Cordillera. On March 12, 1537, Capitan insatiable. In 1650, not satisfied with the Valenzuela held in his hands the first eme rald of prod uction at either Muzo or the neighboring the Somo ndoco (now ChiVOl') deposit. At that Somondoco, the Spanish crown took over
the operation of the mines. In 1675 Somondoco La Pita Mine was permanently closed. The jungle quickly (left) : a 2.5 em overgrew the quarries, and the mine vanished. high eme rald The Spanish monarchy controlled the remaini ng crystal 0 11 calci te from the La mines in spite of temporary closures until at least Pita Min e ill the 1792. By that time, mining operations at Maripi district . Coscuez had also been abandoned follow ing a Sandor F li SS mining disaster that left 300 miners buried in a Coll ection ; Jeff tunnel. Coscuez disappeared. not to be redis Sco vil pho to time, the entire western mining area was in covered until the mid-1 800's. Chivor Mine (right): under habited by the dreaded Muzos and Colirnas; the gro und in the Muisca, known by the Spaniard s as Chibchas, in The Green Way into Modern Times Chi VOl' Mille: a habited the eastern region . The Spanish endured Until J 848 insignificant quantities of emera ld were view of an 111 heavy losses as they fought for control of the mined in Colombia, and in the middle to late J9 emera ld-bearin s emera ld regions, finally breaking into the century, anarchy reigned at the unregulated mines. cal cit e vein. Dietniar territory in 1539. The subjugation of the Muzos, In l 889 the government of Jose Hilario Lopez and Schwer; photo however, took another two decades of heavy the Colombian Congress freed the slaves and fighting. The Spanish finall y defeated the Muzos nationalized most of Colombia' s subsoil. In some
37
South America: Brazil Minas Gerais, Brazil's Top Producer Along With Bahia, Ceara, Golas and Tocantins
Dietmar Schwarz The legendary Serra das Esmeraldas, which venture capitalists, capitalistas, who also share and purportedly lay in the northeastern quadrant of the profits from the workings. The most important Gaston Giuliani state of Minas Gerais, was a strong incentive for and most well-paid miner is the cortador. Relying explore a country Portuguese explorers as they began to exploit the on intuition and experience, the cortador plans and Witll many country during the 16th and 17th centuries. These drives the tunnels. Extraction of emerald from the emerald districts bandeirantes started from the east coast prospect host rock is overseen by the claim owner and is ing inland along the rivers Rio Doce and Rio Je witnessed by the cortador and the capitalistas. quitinonha. They had hoped to find enormous wealth as the Spanish had found in Colombia but Garimpo of Campos Verdes were bitterly disappointed. Even by the beginning A fluid transition from the garimpo mining style to of the 20th century, only very few emerald deposits an organized structure is required to successfully were known in Brazil. All were insignificant and modernize a mine. Operations at the deposit of all lay in the state of Bahia: Brumadinho, Vit6ria Santa Terezinha de Goias are a good example. da Conquista and Bom Jesus. The first economi The mine was a huge garimpo open-pit until 1981 cally interesting finds were not discovered until when it became obvious that the steeply dipping 1963 when the Carnaiba deposits, also in Bahia, emerald-bearing rocks reached great depths. were unearthed. Continuing to follow the veins was technically problematic, and costs were escalating. These Garimpeiros and Capitalistas problems were not addressed by the garimpo Virtually all commercially interesting emerald system and a sociedade, with the required deposits in Brazil, and elsewhere in the world, are technical knowledge and funding, was formed. small, primary deposits. Secondary enrichments, The association built shafts to depths of 200 me such as river sediments, are very rare. A mining ters, modernizing the mine. effort usually begins with a limited open pit and is The people involved in modernizing a mine are worked with simple, hand tools. These quarries due a good deal of credit as the matter is typically are known in Brazil as garimpo, as they are complicated. Claims are frequently small. The worked by garimpeiros (independent miners). complex tectonic structure typical for Brazilian If a deposit is promising, the open pit develops emerald deposits makes it risky to drill deep into underground activities. Underground, the shafts even after test drilling. Horizontal miners follow the veins digging horizontal or displacements and vertical offsets of the rock slightly dipping tunnels that are typically straight are the rule, and the emerald-bearing veins are but that often change direction sharply. These irregular and unpredictable. Though notable tunnels are accessed by galleries at ground level exceptions do exist, if the enormous challenges or by vertical shafts that can be as deep as are to be met, it is generally with the support of 100 meters. Mining is generally done by hand foreign investors. with pick, hammer, chisel and crowbar. Pneumatic In addition to obstacles such as technical know hammers are rarely used. The broken rock is ledge, economics, labor and regulations generally brought to the surface by manual or electric encountered while mining gemstone deposits any winches in buckets or in containers made from where in the world, today mines must adhere to old tires. Miners then carry the debris out of the strict environmental restrictions aimed at mini tunnels in wheelbarrows. mizing the impact of mining activities on the Claim boundaries are marked on the surface and ecological sphere. Environmental constraints are are staked in agreement with the property owner in strongly in place in Brazil and as welcome as these exchange for a share of the mine's proceeds. In regulations are, they are financially and techno addition to the property owner, there are also logically taxing.
46 A Glance at the Economics Piteiras, Capoeiran a), is probably Brazil's most In light of numerous legal, logistic and financial important emerald -producing state. Production constraints, an emerald claim can cost as much as from Santa Terezinha has slowed over the past 2 million US dollars to develop to the point at few years. which it is productive. It costs about 5,000 US Bahia is Brazil's number two producer with the dollars to produce I kg of mine-run emerald. districts of Carnafba and Socot6 contributing to the market to varying degrees since the mid Driving I meter of shaft or tunnel costs an averazeb of 1,000 US dollars in Santa Terezinha and 600 1960's. The Laranjeiras deposit in Carnafba is US dollars in the Carnafba region. remarkable. Though its future is unpredictable, over the last several years, Laranjeiras has pro Such expenses are a function of the nature of the vided high quality emeralds with cut stones as host rock: this factor also determines the large as 5 carats. appropriate mining method and the quantity of As in Colomb ia, production in Brazil has been in emerald that survives the mining process tentionall y reduced while the world emerald mar undamaged. ket suffers a lull in low to intermediate quality Only primary emerald deposits (see page 18) are stone sales. mined: it is the most expensive form of mining and as most emerald crystals are hosted in fresh, hard rock, the eme ralds must be removed with the utmost care. It is easy to imagine how many emerald crystals are damaged or destroyed as the garimpeiros re move the stones from the rock with simple tools. The costs of extraction, in terms of time, money and losses, ensure the future of emeralds, indepen dent of their origin, as an expensive gemstone.
Brazil's Major Mining Districts At the end of the 20th century, Brazil's annual exports of emerald rough officially totaled some SO million US dollars. Today Minas Gerais, including the ltabira/Nova -Era area (Belmont,
The Garimpo ofSanta Terezinha de Goids Traditional emerald mining.' a garimpeiro "carefully" crushes emerald hearing rucks. Left.' A typical garimpo Photos Dietmar Schwarz
47
Emeralds from Asia Pakistan, Afghanistan and India Historically Significant Deposits?
Dietmar Schwarz Though contributing only a few percent of to trade routes such as the Silk Road traversed these and day's world emerald output, Asia once played a valleys. With the road from Pakistan to Gaston Giuliani role as a major producer of emeralds, and the Afghanistan running alongside the Swat River on countries continent's future is promising as deposits from and the Mingora outcropping in plain view from with a localities such as Afghanistan are rediscovered the road, it is likely that these deposits had been green future and developed. Asia's green potential never exploited for years. fades far into the recesses of the collector's mind, as fine and interesting specimens are repeatedly The Mingora District brought to the market. The Islamia Mine in Mingora was the first mining area to be developed after the modern discovery PAKISTAN - Known in Antiquity? of the deposits of the Swat Valley. Little is known Pakistan has several emerald districts: the Swat about the early mining phases, though government Valley in the Northwestern Frontier Province; documents indicate that claims were granted to the Malakand and Mohmand areas (Pranghar, individuals in Karachi and Peshawar and were Gandao, Tsapari, Zankhae, Tora Tigga, Bucha, renewed in three-year terms until 1969. Though Khanori); Bajaur Agency (Amankot, Barang no official production figures were released for Turghao, Maimola) and the Khaltaro area in the that time period, emerald mining was obviously Gilgit district. promising, and the mines were put under control Pakistan's most important emerald region is by of the government run Pakistan Industrial far the Swat Valley. Situated 200 kilometers Development Corporation. This corporation was northeast of Peshawar, Swat is home to a number responsible for mining activity until 1972, when of localities: Mingora, Charbagh, Alpurai, the Sarhad Development Authority took over, Makhad, Malam, Gujarkili, Bazarkot and Bar passing control in 1979 to the new government Kotkai. The largest mines are scattered around agency, Gemstone Corporation ofPakistan (GCP). the northeastern edge of the town of Mingora The GCP developed several regions, discovering (Islamia, Farooq, Correls Trench, Mine 2 and new emerald deposits in Malakand and Mohmand Mine 3). Gujarkili is the second most important as well as the Gujarkili deposit in Swat Valley. In mining district in the Swat Valley. the 1980's, the largest share of Pakistani emerald Swat emerald deposits are generally cited as production came from the Mingora Mine. having been discovered in 1958; however, The GCP was responsible for emerald exploration, scientists in Nancy (France), researching the mining, processing and sales, and quickly learned source of antique jewelry, have found that an that managing an emerald mine is not an easy task, emerald set in a Gallic-Roman earring exhibits and the corporation folded in 1994. A new mining an oxygen isotopic composition known only for license has since been granted to a private compa emeralds from Swat Valley. To many, this dis ny, but at the moment, the Mingora Mine is offi covery proves that Swat Valley emeralds have cially closed as legal issues' are resolved. been mined since antiquity (Giuliani et al, 2000). In the beginning of the 1990's, the Khazana de Though ancient area mining activities are un posit in the Shamozai district was discovered, but documented, we can assume that these emerald it has not been mined on a large scale. deposits have been known and exploited for gen erations. At time of Alexander the Great (about 300 BC), Pakistan and Afghanistan, including the The Gujarkili Deposit Kabul, Swat and Peshawar Valleys, were part of Discovered in 1981 by GCP geologists, the the wealthy kingdom of Gandhara. Extensive Gujarkili deposit is 24 kilometers east-northeast
60 of M ingor a in the valley of a tr ib utary of the Swa t River. According to official estimates, 12,000 carats, a sizable qua nt ity, of gem-qua lity emera lds were produced between 1982 and 1987. In the beginning of October 1997, m ining ri ght s were gra nted by the Direct orate of Indu stries . Commerce and Min eral De velopment of Frontier Pro vince to the pri vately run Balous Gem Min ing . Inc. The com pany immediately began min ing, and w hen the author s vi sited the site in the m idd le of 2000 , a staff of fifty people , including geo logists and min ing engi neers were wor king a 20-hectare area. Today, shafts and tunn els are bored int o the mountainside with a system atic underground operation repl acing the strip mining. Though the comp any does not release prod ucti on figures, the deposit is obviously economical ly intere sting. The mine's enti re produ ction is sold on the American market. Gujarki li emeralds 6 1 New Finds in North Carolina Mike Wise from the Smithsonian Institution in Washington, DC on an old deposit with new potential On the North American continent, small pegmatites me associated with emeralds are found only in the the quartz veins, they rarely contain Yukon, Canada and in North Caroli emerald . na, USA. Only the North Carolina occurrences have produced signifi cant quantities of emerald. Located Significant Events in in the rolling foothills of the Ap Hiddenite Emerald Mining palachian Mountains, the emerald The first discovery of the emeralds deposits of North Carolina occur on from Hiddenite dates back to 1875 Big Crabtree Mountain , near Spruce when green bolts were found in a Pine in Mitchell County. near Shelby cultivated field. In 1880, George in Cleveland County, and at Hidden Fredrick Kunz and William Hidden ite in Alexander County. The most visited Hiddenite in search of plat important of these, in terms of pro inum. Instead. their explorations re duction and gem-quality, are those sulted in the discovery of a few more from the Hiddenite area. At the emerald crystals and hiddenite, the Crabtree and Shelby deposits, emer dark-green variety of spodurnene. In ald occurs in mineralogically simple J Y07, a 276-carat emerald of dark pcgmatites that cut schist, gneiss or green color was discovered on the gabbro. By comparison, the Hidden Ellis property marking the beginning ite emeralds are found in quartz of an emerald rush in the area. Over Above: North American Gem Mine Find veins that cut gneiss, and although the next sixty years. emerald mining Jamie Hill III/earthed neurlv 3,000 carats in the Hiddenite area was almost ofemerald between Thanksgiving and non-existent , that is, until the discov Christmas 1998. ery of a 1,438 carat emerald crystal at the Rist Mine in J969. This re from this parcel, including the 7.85 markable specimen . the largest from carat Carolina Prince (left). the 3.40 North America to date, was followed carat Heart ofCarolina, the J8.88 in 1970 by the discovery of a 59 carat Carolina Queen and the 3.37 carat crystal (Carolina Emerald), re carat Princess ofCarolina. These ported to have color and quality ri emeralds are of a quality comparable valing the famous Muzo emeralds . to those from Colombia. Three In the J980's, over 3,500 carats of years later, a second find of gem emerald were found at the Rist Mine, emerald was made, producing two including a I ,686-carat crystal and a large emerald crystals. estimated at 15.46-carat kite-shaped stone (Kill' 40 to 50 and 100 plus carats , of fine Emerald) considered by some to be quality and rich green color. Mr. the largest and finest-quality emerald Hill is convinced that his recent ever found in North America. spectacular finds are only a glimpse into the rich future of emerald min In 19Y8, James King Hill, Jr. made a ing in North Carolina. significant discovery of gem-quality emeralds at the North American Mineralogy Carolina Prince Gem Mine, formerly part of the Rist Mine. Nearly 3,000 carats of fine Minerals found in the emerald -bear This 7.85 carut emerald set ill (I ring, soldfor $500,000. II wasfound hy emeralds were found including the ing veins include a number of quartz James Hill on III(' "Big Hill " ofthe large uncut 858-carat Empress Caro varieties (clear, smoky and North American Celli Mille. line emerald crystal. Several large amethyst). Frequently. the quartz Private collection and exquisite stones were also cut contains inclusions of brilliant rutile All photos unless otherwise noted hy W(lrren Dobson Above: A 4.5 em high emerald/rum Adams Farm. Paul Tucker collection ; Above: A 2 m deep Jeff Scovi Iphoto layer ofclay is remo Right: Carolina Duchess ved exposing eme A 8.85 carat stone cutfrom rough found bv James Hill rald-hearing veins 011 in 1995011 the Matlock Farm. James Hilf collection. the "Big Hill". crystals. In addition to emerald, the do occur. Etched crystals are com alized solutions. Brown & Wilson cavities contain green beryl, goshen mon and may contain calcite, rutile (200 I) states that the northeast ite and aquamarine. Other minerals and micas growing in the crevices. trending fractures were penetrated include albite, muscovite, black to by pegmatite-derived fluids that ulti dark green tourmaline, single crystals Geology of the Deposits mately crystallized into the quartz or reticulated groups of dark red Despite the over one hundred years and quartz-mica vein that host emer brown rutile and pyrite. Pseudo of mining, the origin of the Hidden ald. Tacker (1999) suggests that morphs of goethite after siderite or ite emerald deposits remains unre orthomagmatic fluids scavenged ankerite are often found in cavities. solved. The local bedrock geology chromium, titanium. iron and car Monazite crystals up to 1.9 ern in of the Hiddenite area consists of Pre bonate from the surrounding rock to length have also been found in asso cambrian schists and gneisses. An aid in the formation of the emerald ciation with the emeralds. Xenotime extensive set of steeply dipping, bearing assemblage. Sinkankas has also been noted, although its oc northeast trending fractures crosscut (1976, 1981) notes that the emerald currence on the properties is rare. the bedrock. Several hypotheses bearing veins of Hiddenite resemble Emeralds from the Hiddenite area have been offered as the origin of the the Alpine clefts of Switzerland, are generally pale green with much emeralds from Hiddenite. Palache et thus, suggesting that the Hiddenite of the dark green coloration restrict al., (1930) suggested that at least veins be considered as hydrothermal ed to a thin outer rim of the beryl some of the emeralds from the area Alpine-type vein instead of peg (the center is commonly colorless or were related to pegrnatites; however, matite. Currently. there is no clear paler in hue). Crystals typically they also acknowledge that some consensus as to the origin of the show simple forms (hexagonal veins are of hydrothermal origin, fol Hiddenite emeralds and further field prisms) with flat terminations, al lowed by the formation of cavities, and laboratory studies are clearly though crystals with complex faces which formed by percolating miner- necessary. 6S ISBN 0-9715371-1-9 .LLl