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Ministry of Mines and Industries of the Democratic Republic of Afghanistan

Afghanistan Geological Survey

Geology and Mineral Resourcesof Afghanistan

Book 2

Mineral Resources of Afghanistan

Report Series

Published by BGS 2008


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Ministry of Mines and Industries of the Democratic Republic of Afghanistan


Geology and Mineral Resources of Afghanistan

Book 2

Mineral Resources of Afghanistan

Editors in chief SH Abdullah, V. M. Chmyriov

Executive editor V. I. Dronov

Report Series

Published by BGS 2008


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Editorial Board:

Sh.Abdullah, N.Azimi, A.Arsalang, M.Girowal, V.I.Dronov, A.Kh.Kafarsky,

A.Salah, N.Sobat, K.F.Stazihilo-Alekseev, G.I.Teleshev, M.Hamid, A.Hashmat,

V.M.Chmriov


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CONTENTS

PREFACE vi

PREFACE TO THE 2008 VERSION vii

INTRODUCTION (V.M. Chmyriov) 1

Chapter 1 Genetic types and ore formations of mineral deposits and 2occurrences in Afghanistan.

Magmatic mineral deposits. (V.M. Chmyriov) 2

Pegmatitic deposits. (V.M. Chmyriov, L.N. Rosaovsky) 2

Carbonatite deposits. (V.M. Chmyriov, G.K. Yeriomenko) 9

Skarn deposits. (V.M. Chmyriov) 11

Hydrothermal deposits. (V.M. Cbayriov) 15

Pyrite deposits. (V.M. Chmyriov) 25

Metamorphogenic mineral deposits. (V.M. Chmyriov) 26

Sedimentary mineral deposits. (M.A. Chalyan, V.I. Dronov) 29

Chapter 2 Metallogenetic epochs. (V.M. Chmyriov) 34

Chapter 3 Metallogenetic zoning of Afghanistan. (V.M. Chmyriov) 36

Chapter 4 General regularities in the distribution of endogenetic 53mineralization in Afghanistan. (V.M. Chmyriov)

Chapter 5 Oil and gas potential. (S.I. Kulakov) 59

Chapter 6 Coal potential. 64

Chapter 7 Hydrogeology of Afghanistan. (E.P. Malyarov) 70

Chapter 8 Mineral and commercial waters. (B.A. Kolotov) 87

Chapter 9 Catalogue of mineral deposits, occurrences, showings and 95mechanical mineralogical haloes.

Fuels. (K.F. Stazhilo-Alekseev, S.I. Kulakov) 95

Metallic minerals. (D.M. Chmyriov, L.N. Rossovsky, K.F. Stazhilo-Alekseev, 102

G.I. Teleshev)

Non-metallic minerals. (V.M. Chmyriov, G.I. Teleshev, L.N. Rossovsky, 199

K.F. Stazhilo-Alekseev)

Salts. (B.K. Lyubimov, M.K. Maywand) 211

Gems and decorative stones. (L.N. Rossovsky, K.F. Stazhilo-Alekseev) 212

Optical material. (K.F. Stazhilo-Alekseev) 214

Building stones. (B.K. Lyubimov, M.K. Maywand). 216

Mineral waters. (E.P. Malyarov) 222


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TABLES 239

FIGURES 269

REFERENCES 284

ANNEXES (located in a separate folder at the back of this volume).


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List of Figures

Figure 1 Geological cross section through the Sarobay Muscovite Deposit (after O.N. Filippov, 1974).

Figure 2 Geological sketch map and cross section through the Jamanak Lithium Deposit

(after L.N. Rossovskiy).

Figure 3 Geological sketch map of the central segment of the Parun Field of Rare-Metal Pegmatites(after. G.K. Eriomenko and L.N. Rossovskiy, 1974).

Figure 4 Geological sketch map and cross section through the Khanneshin Carbonatite Volcano

(after G.K. Eriomenko, 1975).

Figure 5 Geological sketch map of the Maghn Tin Occurrence (after V.S. Kirichek, 1974).

Figure 6 Geological map and cross section through the central and northern segments of the "Tourmaline"

Tin Deposit (after M.F. Rulkovskiy, 1971).

Figure 7 Sketch map of the Okhankashan Copper and Gold Occurrence (after Yu. I. Shcherbina, 1974).

Figure 8 Geological map and cross section through the Bakhud Fluorite Deposit(after V.A. Avtonomov, 1976).

Figure 9 Geological sketch map and cross section through the Shaida Pyritiferous Copper Deposit

(after A.G. Kovalenko, 1973).

Figure 10 Geological cross section through the central area of the Aynak Copper Deposit

(after V.M. Chmyriov, 1975).

Figure 11 Sketch geological map of the Chorqala bauxite occurrence (after S.S. Karapetov et al. 1969).

Figure 12 Geological sketch map-and cross section through the Obatu-Shela Bauxite Deposit

(after Yu. M. Dovgal et al., 1971).

Figure 13 Scheme of Hydrogeological zoning of Afghanistan (after E.P. Malyarov and V.M. Chmyriov, 1976).

Figure 14 Distribution of anomalous concentrations of chemical elements in mineral waters of

Afghanistan (compiled by B.A. Kolotov, 1977).

Figure 15 Administrative division of Afghanistan as of January, 1972.


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List of Tables

Table 1 Types of mercury occurrences.

Table 2 Metallogenetic epoch of Afghanistan.

Table 3 Metallogenetic zones and ore districts of Afghanistan.

Table 4 Relationship between endogenic mineralization and intrusives.

Table 5 Types of tin ore formations.

Table 6 Coal reserves at the main coal deposits and occurrence of the North Afghanistan Basin.

Table 7 Distribution of coal beds by coal accumulation epochs in the Darrah-i-Suf District.

Table 8 Quality of coals From Darrah-I-Suf and Sabzak districts.

Table 9 Coal seams of the Pule-Khumri coal district.

Table 10 Quality of coal from the Pule Khumri coal district.

Table 11 Coal Seams in the Narin-Chal-Namakab coal district.

Table 12 Quality of coal from Narin-Chal-Namakab district.

Table 13 Water yield of Quaternary aquifers from the North Afghanistan Artesian Basin.

Table 14 Water yield from deep wells drilled through Cretaceous deposits underlying the Mazare Sharif

Artesian Basin.

Table 15 Formational pressure in the Upper Jurassic and Hauterivian oil-bearing strata.

Table 16 Pumping test data obtained from wells drilled through the Neogene Aquifer system within theAynak Depression.

Table 17 Water yield of Precambrian crystalline rocks in exploratory adits of the Darband Deposit.

Table 18 Water yield of Precambrian crystalline rocks in exploratory wells of the Aynak Deposit.

Table 19 Water yield of the Quaternary aquifers in the South Afghanistan Artesian Region.

Table 20 General characteristics of mineral waters of Afghanistan.

Table 21 Characteristics of carbonated springs in various belts and zones of Afghanistan

(After V V Kurennoi, V I Belyanin, and B A Kolotov).

Table 22 Characteristics of nitrous thermal water springs of Afghanistan.

Table 23 Characteristics of some sulfur water springs.

Table 24 Characteristics of mineral water springs found in oxidation environment

Table 25 Isotopic analysis of carbonated mineral waters in the Central Panjaw-Gorband Panjsher Zone

Table 26 Main ore districts and mineral deposits of Afghanistan and microelement composition of

carbonated water in the vicinity of the deposits

Table 27 Characteristics of commercial rare-metal-bearing waters from Middle Afghanistan


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List of maps, labelled as Annexes 1 to 9. These are located in aseparate folder at the back of this volume.

Annex 1 Scheme of metallogenetic zoning of Afghanistan, scale 1:4,000,000.

Annex 2 Map of ore deposits and occurrences of ferrous metals and fuel minerals of Afghanistan,

scale 1:4,000,000.

Annex 3 Map of mineral deposits and occurrences of tin, tungsten, molybdenum and bismuth of

Afghanistan, scale 1:4,000,000.

Annex 4 Map of mineral deposits and occurrences of mercury, rare and precious metals of Afghanistan,

scale 1:4,000,000.

Annex 5 Map of mineral deposits and occurrences of non-ferrous metals of Afghanistan,

scale 1:4,000,000.

Annex 6 Map of mineral deposits and occurrences of non-metallic minerals of Afghanistan,

scale 1:4,000,000.

Annex 7 Hydrogeological map of Afghanistan, scale 1:2,000,000.

Annex 8 Map of mineral waters of Afghanistan, scale 1:2,000,000.

Annex 9 Map of mineral and fresh (in deserts) water springs of Afghanistan, scale 1:4,000,000.


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PREFACE

This book describes all the deposits, occurrences and dispersion haloes of minerals discovered in

Afghanistan up to January 1, 1977. It is based on the results of the geological survey and prospecting carried

out by Soviet and Afghan geologists from 1958 to 1977. Account is also taken of all the known work on

minerals carried out by Afghan and West European geologists in the late nineties and in the first half of this

century (up to the sixties). The description is based on a Map of Mineral Resources on a 1:500,000 scale

compiled for the first time for the whole of Afghanistan. The map was published in 1978 by the Leningrad

cartographic factory.

The book consists of two parts. The first part (Chapters I - VIII) deals with genetic types and ore formations

of deposits and occurrences in Afghanistan, metallogenic epochs, metallogenic zoning and general patterns

of endogenous mineralization distribution, oil and gas potentials and the presence of coal, as well as

hydrogeological conditions, mineral and industrial waters. The second part (Chapter II) presents a catalogue

of deposits, occurrences and mechanical mineralogical haloes of minerals in Afghanistan. The bibliography

consists of 161 items. The book contains 27 tables and 15 plates.

Graph Annexes: 1, Scheme of Metallogenetic Zoning of Afghanistan, scale 1:4,000,000; 2, Map of Deposits

and occurrences of Ferrous Metals and Fuel Minerals of Afghanistan, scale 1:4,000,000; 3, Map of Deposits

and Occurrences of Tin, Tungsten, Molybdenum and Bismuth of Afghanistan, scale 1:4,000,000; 4,- Map ofDeposits and Occurrences of Mercury, Rare and Noble Metals of Afghanistan, scale 1:4,000,000; 5,- Map of

Deposits and Occurrences of Non Ferrous Metals of Afghanistan, scale 1:4,000,000; 6,- Map of Deposits and

Occurrences of Non-Metallic Minerals of Afghanistan, scale 1:4,000,000; 7, Hydrogeological Map of

Afghanistan, scale 1:200,000; 8, Map of Mineral Waters of Afghanistan, scale 1:2,000,000; 9, Map of

Mineral and Fresh (in deserts) Water Springs of Afghanistan, scale 1:4,000,000.

The book is intended for geologists engaged in mineral surveys in the Middle East, the whole Mediterranean

Folded Belt and adjacent areas. It may also serve as a geological handbook for students and post-graduates

studying the minerals of Afghanistan.


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PREFACE TO THE 2008 ENGLISH VERSION OF VOLUME TWO

The Geology and Mineral Resources of Afghanistan was compiled and written as a collaborative work

between the Afghanistan Geological Survey and the Soviet Geological Mission. It represents the synthesis of

20 years of joint Afghan-Soviet geological investigations and earlier German and French studies, and in

1980 was formally published in Russian by NEDRA Moscow, in two volumes.

These volumes were translated into English by a group of Professors at the University of Kabul, although thedocuments were not published and the manuscripts archived in the Afghanistan Geological Survey Library.

This version of Volume 2 is a reissue of the English translation, prepared by the British Geological Survey in

2007 as part of an institutional strengthening project for the Afghanistan Geological Survey, funded by the

United Kingdom Department for International Development. A hardback version of Volumes 1 and 2 is

accompanied by a folder containing maps and correlation charts. Volume 2 is also issued in CD form to

accompany a softback version of Volume 1.

The technical and scientific content and text is unaltered from the original and consequently some of the

terminology may be unfamiliar and outdated. Minor reformatting, consistent with a modern, electronically

produced publication, has been made. The diagrams also remain unaltered from the original Russian

publication, and the original large format maps found in the annexes of the original have been scanned andre-printed without change.

Acknowledgements

The following British Geological Survey staff have been involved in the production of this volume: Sarah

Arkley, Antony Benham, Stan Coats, Richard Ellison, Henry Holbrook, Paul Lappage, Bob McIntosh, Paul

McDonnell and Igor Rojkovic. All staff in the Archive Section of the Afghanistan Geological Survey are

thanked for their part in safeguarding the original manuscript through many years of turmoil and conflict.

Mr Abdul Wasy

Director General


November 2007


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INTRODUCTION

This book is the second volume of "Geology and Mineral Resources of Afghanistan". The first volume deals,

in addition to general problems, with stratified and intrusive rock units, as well as with the structural features

of Afghanistan. The second volume deals exclusively with the country's mineral resources.

Until very recently information on mineral resources of Afghanistan was rather scanty. Geological survey

and prospecting carried out in the period between 1958 and 1977 by Soviet and Afghan geologists haveyielded ample information on the mineral potential of the country. Numerous geological data published in

the interim and progress reports have not been systematised or analysed from the regional viewpoint. The

authors have tried to combine all the information available on the mineral re-sources of Afghanistan and

present it in this paper. To ensure appropriate trends of prospecting, the authors give in this book, an

adequate description of all the revealed regularities of different kinds of mineralization. The description is

based on the Map of Mineral Resources of Afghanistan, scale 1:500,000, compiled for the first time for the

whole country (21), as well as on a number of specialized maps at a scale of 1:2,000,000 and 1:4,000,000

(Appendices Nos. 1-9).

The metallogeny of Afghanistan has been only generally considered by many authors (114, 115, 138, 139,

152, 153). The first attempt to summarize the evidence available on the mineral resources is compilation of

Map of Mineral Resources, scale 1:1,000,000 and the explanatory note to it compiled by Soviet and Afghangeologists in 1973 and edited by V.M. Chmyriov and S.H. Mirzad (37, 149).

This work presents a systematic, genetically based description of mineral deposits and occurrences and gives

an assessment of the prospects of potential ore districts, as well as recommendations on further prospecting

and exploration activities in the country. The summaries on the stratigraphy, tectonics and magmatism of

Afghanistan made by Sh. Abdullah, V.I. Dronov, A.Kh. Kafarsky, I.M. Sborshchikov, V.I. Slavin, K.F.

Stazhilo-Alekseev, V.M. Chmyriov and others (45, 144, 48, 50, 38, 132 et al.) served as the basis for the

metallogenetic analysis of the country.

The data obtained by the Soviet and Afghan geologists on the metallogeny of the country are presented in

their publications. These deal with the geology and distribution patterns of the fields of rare-metal pegmatite.

(122-128, 26) deposits and occurrences of tin (25), mercury (27), copper (20,31), uranium and rare earths(155, 160), and fluorite (8). Metallogenetic zoning, ore formations, metallogenetic epochs, metallogenetic

classification of the igneous complexes in Afghanistan and association of the mineralization with magnetism

have been discussed in other papers (87, 115, 147, 148, 29 and others).

This work is based on evidence collected by the authors over many years of their work in Afghanistan, as

well as on previous publications. The authors have, in particular, used the geological survey results obtained

by Y.P. Azhipa et al. (10), Sh.Sh. Denikayev at al. (39, 41), A.B. Diomin (42), Yu.M. Dovgal et al. (42), V.I.

Dronov et al. (43-46), A.Kh. Kafarsky et al. (71-73), S.S. Karapetov et al. (75, 76), V.P. Kolchanov et al.

(81), A.Ya. Kochetkov (75, 43, 44, 45, 76), Yu.M. Koshelev et al. (86), K.Ya. Mikhailov et al. (102, 103),

Y.M. Moraliov et al. (106), L.N. Rossovsky (40, 41, 120), L.M. Sborshchikov et al. (129, 130), V.I. Slavin et

al. (142), K.F. Stazhilo-Alekseev (74, 75), I.I. Sonin (75, 42), D.A. Starshinin et al. (146), V.P. Feoktistov

(29-41), M.A. Chalyan (42), A.S. Shadchinev et al. (134, 135) and others; prospecting and exploration werecontributed to by V.A. Avtonomov et al. (9), I.I. Galchenko et al. (55), G.K. Eriomenko (159), V.I.

Efimenko et al. (157, 158), O.N. Kabakov et al. (69), V.S. Kirichek et al. (79), L.E. Kornev et al. (84, 85),

I.K. Kusov et al. (90), K.I. Litvinenko et al. (91-93), G.A. Orlov et al. (112, 113), G.G. Semionov et al.

(133), R.M. Khasanov et al. (78), Yu.I. Shcherbina et al. (140, 141) and others. Because of the different

amount of details contained in the studies, as well as the shortage of information, available on a number of

mineral deposits and occurrences, some of the conclusions and recommendations that follow should be

considered preliminary.


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Chapter 1 GENETIC TYPES AND ORE FORMATIONS OFMINERAL DEPOSITS AND OCCURRENCES IN AFGHANISTAN

The term ore formation used in formation analysis implies a group of ore deposits of similar mineral composition

formed under essentially identical conditions [52]. Ore formations are occasionally subdivided into mineral types,

since some deposits included in the same formation have different mineralogical and geochemical properties. The

mineral deposits of Afghanistan are classified as magmatic, pegmatitic, carbonatitic, skarn, hydrothermal,metamorphogenic and sedimentary types. These genetic types include various ore formations [30, 37]

(Appendices 2-6). The metallogenic zones and ore districts mentioned below are shown in Appendix 1.

Magmatic Mineral Deposits

The magmatic mineral deposits of Afghanistan are genetically associated with ultrabasic rocks (chromite

formation) and basic rocks (magnetite-ilmenite formation).

Chromite formation

Chromite ore deposits and occurrences are found in massifs of Eocene ultrabasic rocks in the Region ofAlpine Folding (e.g. Logar, Shodal and other deposits). These are confined to the differentiated massifs of

ultrabasic rocks [130, 141], whose lower portions are composed of dunite, grading upwards into pyroxenite

(30, 130). Lens-like chromite ore bodies are commonly localized in dunites and exhibit well-defined

boundaries with the country rocks. The ore contains from 42.4 to 53.5 per cent chromium oxide. The ore can

be classified into the following principal types: massive, nodular and disseminated, all being medium-

grained in texture. The major mineral association found in the deposits and occurrences of this formation

consists of chromite, magnesio-chromite, olivine, spinel, enstatite, magnetite, serpentine, garnet, chrome-

chlorite, talc, opal, and chalcedony.

Apart from the Eocene ultrabasic rocks, Early Carboniferous-Permian and Early Cretaceous ultrabasic rocks

have also been found in Afghanistan. The former are associated with the Hercynian geosyncline, and the

latter, with the deep fault zones of the South Afghanistan Median Mass. Chromite ore occurrences areassociated with the Early Cretaceous ultrabasic rocks, but no commercial concentrations were discovered

and these are generally considered unpromising [107].

Magnetite-ilmenite formation

The mineral occurrences of this formation are associated with Early Cretaceous differentiated massifs of

gabbro-monzonite-diorite composition extending in Proterozoic rocks along the Paghman fault block (the

Paghman ore deposit and others). The ore bodies are lens-like and tabular, consisting of magnetite, ilmenite,

anatase, brookite, apatite and minerals of the country basic rocks. The iron content of the ores varies from 25 to

50 per cent, and that of titanium oxide from 1 to 5 per cent. Occurrences of the magnetite-ilmenite formation

associated with Early Cretaceous basic rocks have also been established in the Nurestan Block [40].

Pegmatitic Deposits

Pegmatites are widely distributed in Afghanistan, occurring mainly in median masses. There are muscovite,

rare-metal-muscovite and rare-metal pegmatite formations.

Muscovite pegmatite formation

Muscovite pegmatites are in a close spatial relationship with Proterozoic rocks metamorphosed under the

conditions of the kyanite-muscovite-quartz subfacies of the amphibolite facies. These occur primarily in the

Nurestan-Pamir Median Mass and in the north of the South Afghanistan Median Mass. All the know

muscovite pegmatite fields are confined to the domes and limbs of anticlinal folds. It has been established


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[53] that commercial muscovite-bearing pegmatite bodies are essentially of plagioclase composition and

occur only in biotite and garnet-biotite plagiogneiss (Sarobay, Tokana and other deposits).

The Sarobay deposit [53] includes three types of pegmatite vein: (1) mica-bearing plagioclase pegmatite of an

undifferentiated structure, containing commercial muscovite concentrations; (2) large bodies of undifferentiated

fine-grained microcline-plagioclase pegmatites with near-contact micaceous zones (of no commercial value);

(3) mica-free dyke-shaped pegmatite bodies of plagioclase-microcline-tourmaline composition. The muscovite

pegmatites of the first type are lenticular, tubular and laminar (Fig.1). These vary from 10 to 120 metres inlength, from 0.5 to 10 m in thickness and extend from 6 to 27 metres down the dip. The contacts between the

veins and country rocks are distinct. Pegmatites of quartz muscovite replacement and pegmatoid bodies may be

found. In the former, muscovite occurs in short, columnar, platy, hexahedral crystals, 3 to 4 centimetres thick,

and up to 15 centimetres across. The pegmatoid bodies may have large wedge-shaped muscovite crystals 20 by

20 centimetres in size and 5 to 7 centimetres in thickness. These are confined to the boundary between the

quartz core and granular feldspar aggregate. Apart from quartz, oligoclase, and muscovite, both pegmatite

varieties contain schorl, almandine, biotite and apatite. The specific structural pattern of the Sarobay deposit is

typical of other deposits and occurrences of muscovite pegmatites.

Formation of rare-metal muscovite pegmatites

The deposits of this formation are associated with pegmatite fields in exocontact zones of Oligocene granitebatholiths (Paghman complex, Nurestan-Pamir Median Mass).

The pegmatite bodies of the Pachagan deposit occur in Proterozoic gneiss and para-amphibolite. These fall

into three classes according to the type of mineralization and structural patterns (1) zonal pegmatites with

muscovite-beryl mineralization; (2) intensively albitized massive pegmatites with finely disseminated beryl

mineralization; (3) barren pegmatite bodies of a massive, locally zonal structure. The pegmatite bodies are

sheet-like in shape, varying in thickness from 0.3 to 10 metres and in length from 40 to 1,000 metres. The

pegmatite bodies have distinct contacts with the country rocks. The structural pattern of the pegmatite bodies

of the first type is complex. At the contact, fine-grained pegmatite occurs, grading into a coarse-grained

variety. The cores of the veins are composed of quartz and feldspar blocks. In the albitized zones, the quartz

content goes up to 40 per cent, and beryl crystals up to 30 centimetres in diameter are encountered. Apart

from the basic minerals, the pegmatites of this type include minor quantities of biotite, almandine, schorl,apatite and zircon. The size of the muscovite crystals varies from 10 to 100 sq. cm.

Formation of rare-metal pegmatites

Large fields of rare-metal pegmatites with commercial concentrations of tantalum, niobium, lithium, cesium,

beryllium, tin and precious stones were discovered and to a certain extent studied (120, 122-128).

The pegmatite fields are widespread mainly in the Nurestan-Pamir, and to a lesser extent in the South

Afghanistan Median Mass, where they are spatially and genetically associated with the granitic batholiths of

the Laghman and Helmand complexes. Rare-metal pegmatites also occur in the Region of Hercynian

Folding, where they are closely associated with granitic rocks of the third phase of the Hendukush complex.

The rare-metal pegmatite veins found in the Nurestan-Pamir Median Mass are associated with the biotitic andbinary granites of the third phase of the Laghman complex. The host rocks for the rare metal pegmatites are

represented by phyllite-like quartz-micaceous schists containing andalusite, cordierite, garnet and staurolite.

Less common are pegmatite veins in diorite and granodiorite massifs of the first phase of the Laghman

complex; in garnet-sillimanite-biotite gneiss and marmorized limestone these are even less widespread. The

largest and most intensively mineralized pegmatite bodies are generally localized in phyllite-like schists. The

morphology of the rare-metal pegmatite bodies exhibits a great variety, but most common are veins with swells

and tabular bodies. The pegmatite bodies also vary greatly in size: from 1 to 60 metres in thickness and from a

few dozen of metres to 2-5 kilometres in length. Some of the bodies are very large: for instance, vein No. 8

(albite pegmatite with lepidolite and spodumene) from the Nilaw field extends for 4 kilometres, with the

average width of 4 metres; the spodumene-albite pegmatite vein of the Drumgal deposit extends for more than

1,500 metres, averaging 30 metres in width; the albitized microcline pegmatite vein from Kulam, enclosing

lepidolite and spodumene pockets, extends for more than 3,000 metres, varying from 5 to 40 metres in width.


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The internal structure of the pegmatite bodies is massive, banded, zonal or slightly zonal. The zonal structure

may only be observed in bodies of poorly replaced microcline pegmatites.

The rare metal pegmatites of Afghanistan are subdivided into the following main types according to the

principal rock-forming and typomorphic minerals; (1) oligoclase-microcline biotite-muscovite pegmatites

with schorl and some beryl (barren); (2) albitized microcline pegmatites with schorl, muscovite and beryl

(coarse-crystalline hand-sortable beryl ore); (3) albitized microcline pegmatites with pockets of blue

cleavelandite, lepidolite, spodumene and polychromatic tourmaline (deposits of kunzite, vorobyevite,tourmaline and rock crystal); (4) albite pegmatite :with lepidolite, tantalite, spodumene and pollucite pockets

(tantalum ore); (5) spodumene-microcline-albite and spodumene-albite (spodumene) pegmatites (rich lithium

ore); (6) lepidolite-spodumene-albite pegmatites with polychromatic tourmaline, tantalite and pollucite

(cesium and tantalum-cesium ores).

A certain pattern has been established in the distribution of different pegmatite veins with respect to the

massifs: as the distance from the granites increases, the veins of essentially microcline pegmatites are

successively replaced by albite, spodumene-albite and lepidolite-spodumene-albite pegmatites.

The rare metal pegmatite veins within the Nurestan-Pamir Median Mass occur in fields with an area ranging

from 10 to 800 sq. km: 21 fields of this kind are already known. Dozens, or less commonly hundreds, of the

rare-metal pegmatite veins occur within the fields. Three structural types of fields can be distinguished: (1)those consisting of tabular, gently-dipping veins normally found in gabbro-diorite massifs, where the veins

are mostly confined to the contraction fissures developed in the endocontact zones. Such veins are less

common in gneiss; (2) fields of tabular, steeply dipping veins confined to deep-seated fracture zones in

quartz-mica garnet-staurolite schists. The largest veins and veined zones of spodumene pegmatites may be

encountered in the fields of this type; (3) ones with lenticular veins, generally imbedded in schists crowning

dome-shaped granite massifs. Fields of the first and second types are most common.

The strongly dissected topography of the Badakhshan, with relative elevations of 1,000 to 3,000 metres,

makes it possible to trace the zonal arrangement of the ore deposits down the dip to a considerable depth. For

instance, in the Jamanak ore deposit, (Fig. 2) a zone of steeply dipping spodumene bodies is exposed to a

depth of 1,450 metres down the dip. Large tabular spodumene pegmatite bodies occur within an elevation

range of 4,650 to 3,750 metres. Down the dip, from a level of 3,750 to 3,000 metres, these are replaced byalbite pegmatites. The Drumgal deposit is exposed to a depth of 1,500 metres, where spodumene pegmatites

are encountered within the elevation range of 4,000 to 3,400 metres. Downwards, within the 3,800-3,300

metre range, these grade into albite pegmatites including spodumene-albite in small pockets. The lowest

interval of the veined zone consists of oligoclase-microcline biotite-muscovite pegmatites containing coarse-

crystalline alkali-free beryl.

The mineral composition of the rare-metal pegmatites in Afghanistan is complex. Microcline, quartz, albite,

spodumene and petalite are the principal rock-forming minerals. Of secondary importance are muscovite,

biotite, lepidolite, protolithionite, tourmaline, pollucite, amblygonite-montebrasite, triphylite-lithiophylite,

triplite, lazurite-scorzalite, sicklerite, tegerosite, purpurite, almandine, spessartite, staurolite, andaluzite,

sillimanite, scapolite, beryl and ankosine-gilbertite. Accessory minerals are represented by cassiterite,

columbite, niobite-tantalite, tantalite-columbite, tantalite, mangano-tantalite, microlite, herderite, magnetite,ilmenite, sphene, zircon, monazite, xenotime, topaz, rutile and apatite.

Of particular interest is the Tagawlor pegmatite field located in the Helmand zone in the margin of the South

Afghanistan Median Mass. This is a linearly elongated, nearly east-west-trending zone of steeply dipping

tabular pegmatite veins with spodumene pegmatites markedly prevailing. Microcline schorl-muscovite and

cymatolite-albite pegmatites occur also. The pegmatite veins forming the field are found in the contact zone

of a large massif of biotite granodiorites and granites of the Helmand Complex, primarily in Upper

Proterozoic quartz-chlorite and quartz-chlorite-biotite schists. The pegmatite veins show a certain pattern in

their spatial distribution. The veins of spodumene pegmatite are replaced by cymatolite-albite along the

strike of the zone, from east to west. The veins of microcline schorl-muscovite pegmatite are widespread in

exo- and endocontact zones, while the spodumene-pegmatite veins tend to be localized only in exocontact

zones. More than 200 steeply-dipping spodumene pegmatite veins concordant with the country rocks are

known within the field. The veins vary from 100 to 1,500 metres in length and from 1 to 20 metres in

thickness, and exhibit distinct contacts with the country rocks. The zones of near-vein altered country rocks


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do not extend more than 1-5 centimetres from the contact, the alteration consisting in a slight

muscovitization and an increase in apatite and tourmaline content. The principal mineral assemblages

composing the pegmatite bodies are as follows: spodumene-microcline-quartz-albite complex; microcline

pseudomorphs of spodumene and quartz after petalite-albite; albite aggregate. The specific features of the

Tagawlor spodumene pegmatites are given below: (1) a tabular shape and steep dip of the pegmatite bodies;

(2) a banded, patchy or massive internal structure of the bodies with no zonal pattern; (3) half of the early

spodumene consists of spodumene and quartz pseudomorphs after petalite, indicating that this was originally

spodumene-petalite pegmatite; (4) the bands composed of the coarse-crystalline varieties of long-prismaticspodumene, microcline and quartz contain at least 15-25 per cent quartz; the bands composed of spodumene

and quartz pseudomorphs after petalite and microcline include no quartz aggregates; the cleavelandite and

lamellar albite aggregates replacing microcline, early spodumene and pseudomorphs of quartz and

spodumene after petalite exhibit evidence of lithium redeposition resulting in the formation of peculiar, fine-

grained spodumene-albite and spodumene-amblygonite-albite aggregates; a replacement of spodumene by

fine-grained ankosine-gilbertite aggregate is fairly common.

The spodumene pegmatites of the Tagawlor field were formed in a linearly elongated deep fracture zone in

hornfels and schists. The tabular shape, considerable extension and limited thickness of the pegmatite bodies

suggest a high penetrating ability of pegmatite-forming melt solutions, owing to their fusibility and mobile

character. The orientation of the long prismatic spodumene crystals as well as quartz and spodumene

pseudomorphs after petalite perpendicular to the pegmatite body contacts indicates that crystallization ofmelt-solutions occurred in tension fissures under a certain lithostatic pressure typical of a given depth level

[120]. Spodumene pegmatite veins may be found in a narrow band of quartz-feldspar-biotite hornfels, 1.0-

1.5 kilometres wide, extending along the exocontact of the granite massif. The spodumene pegmatite veins

are never encountered in schists, whose grade of metamorphism does not exceed that of green schists, nor in

granites. Consequently, the thermodynamic conditions in the narrow zone of contact metamorphism were

obviously most favourable for the formation of spodumene pegmatite veins, this allowing a rough estimation

of the initial crystallization P-T conditions of pegmatite melt solutions. Judging by the composition of the

hornfels, these conditions generally correspond to an amphibole-hornfels facies of contact metamorphism

[126], characterized by pressures of several hundred to 3,000 atmospheres and temperatures of 500 to 600C.

The Tagawlor spodumene pegmatites are noted for the banded alternation of spodumene and initially

petalitic aggregates inside the pegmatite bodies. This can be explained by a variation of SiO2 concentration

under similar P-T crystallization conditions. Subsequently, petalite becomes an unstable phase and changes

normally into spodumene and quartz as the temperature drops. The initially petalite-spodumene composition

of the Tagawlor pegmatites and subsequent transformation of petalite into spodumene and quartz suggest

that these were formed at a relatively small depth (3.0-3.5 km) [121].

The large field of spodumene pegmatites discovered in the Helmand zone and the wide distribution of

pegmatites and granites in the Helmand complex indicate that the Helmand-Argandab Uplift is promising

source of rare metals.

Distribution by rare metal

The pegmatite fields of Afghanistan include veins with commercial concentrations of lithium, tantalum,

cesium, beryllium, tin, precious stones and piezo-optical raw materials. 50 per cent of the fields discoveredhave pegmatite bodies with workable spodumene concentrations. Tantalum, beryllium and tin mineralization

is less common. Cesium minerals, precious stones and piezo-optical raw materials have been found only in

some of the veins.

Lithium

Commercial concentrations of lithium have been encountered in the Paron, Shamakat, Tagawlor,

Eshkashem, Alingar, Marid and Nilaw-Kulam fields of rare-metal pegmatites. The Paron ore district, with an

estimated 3 million tonnes of lithium oxide, is most extensive. The veined zones run for 2 to 7 kilometres in

length, with a total thickness of the ore bodies up to 70 metres. Some of the veins, 20 to 40 metres thick,

extend for 1.0-1.5 kilometres. The spodumene content in spodumene-albite ore varies from 15 to 35 per cent.

The average content of lithium oxide in the deposits of the Paron ore plexus is 1.5 per cent. With respect to

total lithium oxide reserves, Afghanistan comes second after Canada.


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Tantalum

Tantalum occurrences represented by tantalite, niobium-tantalite, manganotantalite and microlite have been

found in the Nilaw-Kulam, Darrahe-Pech, Darrahe-Nur, Paron, Kantiwa, Shahidan, Alingar, Talbuzanak,

Pachigran, Marid and other fields of rare metal pegmatites. As far as it is known at present, most promising

for tantalum are albite pegmatites with pockets of spodumene, lepidolite and polychromic tourmaline

occurring in Nilaw. The albite pegmatites are found in four flat-lying tabular bodies, each 2 to 7 metres thick

and 3 to 4 kilometres long. Veins of similar composition occur in Darrahe-Pech.

Some stretches of the gigantic zones of spodumene pegmatite veins from the Paron ore plexus (Pasgushta,

Jamanak, Drumgal deposits) are highly promising for tantalum. These zones are very extensive: in places

they are highly albitized and greisenized and contain rather high concentrations of tantalum minerals and

cassiterite. For example, in the Drumgal deposit, the content of tantalum pentoxide is 0.06 per cent, the

thickness of the spodumene vein averaging 30 metres and the tantalum niobium ratio being 5:1 [120]. The

spodumene-microcline-cleavelandite pegmatites of the Wazgul deposit often contain tantalite crystals

weighing 5-7 kg. The content of tantalum pentoxide in the spodumene veins of the Tagawlor pegmatite field

averages 0.013 per cent, the tantalum-niobium ratio being 2.5:1. Analysis of the distribution of tantalum

mineralization in the pegmatite fields of Afghanistan shows that, ceteris paribus, (favourable types of

pegmatites and mineral assemblages), the flat lying pegmatite bodies are most promising for tantalum.

The widespread tantalum mineralization, characteristic paragenesis of elements (lithium-tantalum-tin-

cesium), extensive areas of lithium mineralization in spodumene pegmatites, and tantalum-bearing types of

rare metal pegmatites suggest that the southern part of the Nurestan Pamir Median Mass is highly promising

for tantalum.

Cesium

Cesium mineralization has been detected in seven pegmatite fields: Paron, Milaw-Kulam, Shamakat,

Alingar, Surkh Rod, Darrah-Pech and Kurgal. The highest cesium content was found in the Tatang vein of

the Surkh Rod field. Pollucite in this vein forms lenses, pockets and veinlets of fine-grained massive

aggregates in the pollucite zone. Such inclusions are as large as 20 by 100 metres. The average pollucite

content in the zone is 25-30 per cent and that of cesium oxide, 9 per cent. The lepidolite-amblygonite-albite

veins from the Kalatan deposit have been found to contain 18 cu m pollucite blocks. As the cesium-bearingpegmatites have not been studied thoroughly, it is difficult to evaluate them commercially, but the flat-lying

spodumene-microcline-cleavelandite veins are of some interest since they contain pollucite and tantalum,

found in the Paron and Kantiwa fields and in the west of the Darrahe-Pech field.

Beryllium

The pegmatite fields of Nurestan contain all the varieties of beryl usually found in pegmatites early alkali-

free beryl, sodium beryl, sodium-lithium beryl, lithium-cesium beryl and a number of rare beryllium

minerals, such as herderite, moraesite and several beryllium phosphates so far unidentified. Commercially

valuable pegmatite veins with coarse-crystalline beryl are found in the Nilaw-Kulam, Pachagan, Darrahe-

Pech and Darrahe-Nur fields. High concentrations of coarse-crystalline beryl have been encountered in

albitized microcline veins from the Paron pegmatite field.

The pegmatite fields of Eastern Afghanistan, particularly lithium deposits and large veins of albite

pegmatites, have large amounts (dozens of thousands of tonnes) of poor, finely impregnated beryl ore

containing 0.05-0,08 per cent beryllium oxide [109].

Precious stones and piezo-optical raw materials

The chief precious stones found in rare-metal pegmatites include kunzite, variously coloured tourmaline,

vorobyevite, aquamarine and emerald. Occurring in limited quantities, emerald is found in small veins of

disiliconized pegmatites (Badel deposit). Kunzite is a very rare precious stone that is mined regularly only in

Afghanistan. The rare-metal pegmatites of Afghanistan are unique with respect to the distribution and

content of precious kunzite varieties. Kunzite occurs in the pegmatite bodies of the Nilaw-Kulam, Darrahe-

Pech and Kantiwa fields. The most valuable and largest kunzite accumulations have been found in the Kulam


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pegmatite vein, which can undoubtedly be regarded as a unique deposit of this mineral. During the

exploration of this deposit in 1974 alone over 1,000 kg of kunzite were recovered.

The Kulam deposit is located at the eastern exocontact of a large binary granite massif within the Nilaw-

Kulam pegmatite field. The rare-metal pegmatites are genetically associated with the granites. The pegmatite

veins occur in gneiss, crystalline schist and gabbro-diorite. The gneiss and schist contain several hundred of

concordant, steeply-dipping; pegmatite veins with bulges. About 70 veins in the gabbro-diorite are gently-

dipping and tabular. According to their mineral composition, the veins are subdivided into the followingtypes: (1) oligoclase-microcline with schorl and beryl; (2) albitized microcline with schorl and beryl; (3)

albitized microcline with schorl, beryl, lepidolite, polychromatic tourmaline, spodumene, pollucite, kunzite

and rock crystal; (4) albite with lepidolite, polychromatic tourmaline, spodumene, occasionally with kunzite;

(5) lepidolite-spodumene-albite. The veins of the first and second types occur in crystalline schist and gneiss.

The gabbro-diorite massif includes veins of the second, third, fourth and fifth types. As the distance from the

source granite massif increases (north-southwards), the microcline pegmatite is replaced by the albite variety

and, eventually, lepidolite-spodumene-albite veins. The Kulam deposit is the eastern mineralized portion,

1,200 metres long, of a large albitized microcline pegmatite vein running for approximately 4 kilometres.

Numerous offshoots branch off from the main vein, which varies in thickness from 4 to 40 metres; the

offshoots range from 2 to 10 metres in thickness and from 200 to 400 metres in length. The vein and

offshoots occur in massive gabbro and gabbro-norite. The vein exhibits distinct contacts with the countryrocks. The wall rock alterations are slight, the mafic minerals in gabbro being replaced by protolithionite and

apatite within 1-3 centimetres from the contact. The Kulam vein, intricately and irregularly differentiated, is

composed of the following mineral assemblages: (the volume of the vein is parenthesized) high albitized

quartz-muscovite aggregates (2 per cent); biotite-microcline block pegmatite (10 per cent); quartz-microcline

gigantic-block pegmatite (5 per cent); quartz-spodumene block pegmatite (2 per cent); albitized muscovite-

microcline block pegmatite (55 per cent); fine-grained aggregates of saccharoidal albite and cleavelandite

with a quartz muscovite assemblage (18 per cent); muscovite-cleavelandite assemblage (5 per cent);

mineralized pockets and zones with cavity fillers, actually aggregates of blue cleavelandite, lepidolite,

polychromatic tourmaline, rock crystal, kunzite and other minerals (5 per cent). The internal structure of the

main portion of-the gently-dipping vein-is asymmetric-zonal. Fine- and medium-grained aggregates of

saccharoidal albite and cleavelandite with quarts muscovite replacement occur at the foot wall. Above, there

is a zone of albitized muscovite-microcline pegmatite of a block-patch structure and, finally, at the uppercontact of the vein, there is an intermittent zone composed of quartz-microcline pegmatite of a large- and

gigantic-block structure, some microcline crystals reaching 5 m in size. The thickness of the above

mentioned zones is a few metres, less often, dozens of metres, depending on the total thickness of the vein.

Biotite-microcline block pegmatite occurs separately; composing the eastern portion of the vein, 150 m long.

Quartz-spodumene large-block aggregates and beryl-rich patches are also locally distributed. The internal

structure of the pegmatite body is characterized by an abundance of small (5-10 cm) cavities filled with

poorly shaped quartz, microcline, muscovite and comb-like albite crystals.

The mineralized pockets and zones enclosing aggregates of blue cleavelandite, lepidolite, polychromatic

tourmaline, rock crystal and kunzite occur sporadically and are randomly distributed. The largest mineralized

zone is localized in an offshoot of the vein. Two types of mineralized zone can be distinguished; the first is

found in the albitized muscovite-microcline block pegmatite; the second, in the biotite-microcline blockpegmatite. Zones of the first type are composed of inequigranular rock consisting of microcline and quartz

blocks, as well as of white-pink disk-like spodumene crystals. The interstitial space between the microcline,

quartz and spodumene is filled with aggregates of blue cleavelandite and lepidolite. The size of the

microcline and quartz blocks varies from 10 to 100 cm in cross section, and that of the spodumene crystals

from 0.5 by 1 by 3 to 4 by 5 by 70 cm. The rock under consideration is characterized by the constant

presence of cavities, varying in size from 2-10 to 40-50 cm. In these cavities there are crystals of microcline,

rock crystal, comb-like albite, cleavelandite, kunzite, pollucite and vorobyevite.

In the most intensely mineralized cavities, the space between the large crystals of the minerals mentioned

above is filled with porous, flaky aggregates of lepidolite, thin-fibre hair-like aggregates of light green

tourmaline and white clay matter. Less common are cassiterite, mangano-tantalite, microcline (several

varieties), acicular petalite, herderite and some unidentified tantalum minerals of a high specific weight.


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The mineralized zones of the second type are confined to the cavities in the biotite-microcline block

pegmatite occurring at the hanging wall of the vein. The diameter of the cavities ranges from 0.5 to 1.5-2.0

m. The microcline blocks surrounding the cavities at a distance of 0.5-0.7 m contain no graphic or

apographic quartz intergrowths, well-developed crystals of them forming the walls of the cavities. Many

microcline crystals are strongly leached out from inside the cavities. Rock crystals with a short-columnar

habit grow, along with microcline, inwards into the cavities. These crystals are as large as 40 cm in length

and 20 cm in diameter. Mineral aggregates consisting of blue laminated cleavelandite, muscovite, lepidolite,

pink spodumene, vorobyevite, kunzite and pollucite generally occur inside the cavities, replacing microclineand growing on it. This mineral aggregate is distributed rather irregularly. Kunzite occurs in mineralized

zones and pockets, inside the cavities and around them. It is found in paragenesis with lepidolite, blue

cleavelandite, rock crystal, vorobyevite, and occasionally with pollucite. The largest amount of kunzite has

been recovered from large cavities. The content of kunzite in the mineralized zones with cavities is irregular.

Kunzite crystals are usually tabular (thick-tabular, short-prismatic, long prismatic, laminar and discoidal).

The common forms of the crystals are (100), (110), (120), and (130). Well-developed crystals have a

pronounced "head" of a (021), (111) or (221) form. Most crystals exhibit a well faceted vertical striation. The

light-pink, transparent kunzite has Ng = 1.657, Nm = 1.662, Np - 1.658, Ng - Np = 0.017 and +2v = 56.

The crystals of the jewellery kunzite from the Kulam deposit vary in size from 0.5 by 1.0 by 1.5 cm to 3 by

15 by 35 cm. The transparent kunzite crystals show a great variety in colours pink-violet, crimson, red-violet,

cerise, greenish-lilac, lilac, dark bluish green, blue, bluish-green, green, yellowish-green and yellow.

Polychromatic crystals with any combinations of the above shades, as well as transparent colourless crystals,

are common. The transparent coloured crystals are noted for their marked dichroism, the crystals deepening

in colour along the symmetry axis and being, almost colourless in the direction perpendicular to the axis.

Two processes are responsible for the formation of kunzite crystals in the Kulam deposit. (1) Regeneration of

white-pink spodumene found around and partly inside the cavities. The effect of residual hydrothermal

solutions is responsible for the first process. As a result, white-pink spodumene was dissolved and in a way

purified (regenerated). Inside a large, opaque, white-pink spodumene crystal, one or several smaller

identically-oriented, transparent kunzite crystals are formed with a characteristic etch pattern. The ends of

the crystals are dissolved first, thus allowing the formation of conspicuous etch pits on them. (2)

Spontaneous crystallization in cavities. In the process, microcline crystals are overgrown with kunzite

crystals; all the other minerals (comb-like cleavelandite crystals, rock crystal and vorobyevite crystals,

lepidolite aggregates, pollucite crystals and aggregates) appear to have formed later than the kunzite.

The study of a large number of the rare-metal pegmatite fields in Afghanistan has made it possible to

establish the following indications of kunzite deposits: (1) kunzite deposits are formed in flat-lying pegmatite

veins occurring in massive rocks, such as gabbro-diorite or quartz diorite; (2) kunzite-bearing pegmatite

bodies consist of albitized microcline pegmatites including pockets and mineralized zones of lepidolite,

polychromatic tourmaline and white-pink spodumene; (3) kunzite-bearing pegmatite bodies show an

irregular internal structural pattern. These bodies are usually differentiated. They are notable for their block

to gigantic-block structural pattern, as well as for the conspicuous development of small cavities. No kunzite

is formed in pegmatite veins of a similar type occurring in schists and gneisses within the same fields.

Neither does it occur in intensely mineralized spodumene lepidolite pegmatites containing polychromatic

tourmaline, pollucite and tantalum minerals. Thus kunzite requires extremely stable conditions of pegmatite

body formation and the presence of an appropriate content of volatiles and rare elements in the pegmatite-

forming melt-solutions.

Another genetic type of kunzite deposit is known from the Darrahe-Pech pegmatite field [120]. A small

massif of aplite-like granite-albitite contains schlieren pegmatite with mineralized pockets (cavities), where

high concentrations of blue cleavelandite, tantalite, lepidolite and kunzite have been detected.

Coloured transparent tourmaline occurs in cavities found in the mineralized pockets inside albitized

microcline pegmatite bodies. The paragenesis of the tourmaline is similar to that of kunzite. The transparent

tourmaline and kunzite occur in the same pegmatite bodies. In addition, pegmatite veins containing only

transparent tourmaline (with no kunzite) have been found at the Paprok deposit in the Kurgal pegmatite field

and in the upper reaches of the Darya-i-Peshgul River, in the Paron pegmatite field. The transparent

tourmaline varieties are green, blue and pink in colour. The crystals vary from 1 to 20 mm. in diameter and


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from 10 to 120 mm. in length. Large pink-green transparent crystals reaching 7 cm in diameter and 35 cm in

length are less common.

The vorobyevite and aquamarine occurring in a genetic association with coloured tourmaline and kunzite are

more rare than these minerals. The crystals of vorobyevite and aquamarine vary in size from 1 by 1 to 5 by

10 cm; they are transparent and translucent, of a beautiful cream and sky-blue colour.

Piezo-optical quartz also occurs in genetic association with green tourmaline and kunzite inside the cavitiesand vugs in albitized pegmatites. The largest crystals of rock crystal have been found in the Kulam deposit

and in the veins of the Kantiwa field. Some of the perfect crystals from the Kulam deposit attain 30-40 kg. in

weight. The technological testing of the rock crystal has shown that these are suitable for the manufacture of

piezo-optical articles.

Carbonatite Deposits

During some special investigations performed by G.K. Yeriomenko, B.Ya. Vikhter, and V.M. Chmyriov, a

volcanic carbonatite complex was identified in the central part of the late-orogenic Seystan Depression, filled

with Neogene-Quaternary sediments [155, 160]. The Khanneshin carbonatite volcano is located in a slightly

uplifted fault block. In the west and east, it is bounded by a S-N-trending fault system, whereas in the north,by an E-W trending fault. These deep-seated structures are distinguishable on a magnetic field map.

Carbonatite volcanism may be assigned to the Early Quaternary on the basis of finds of Neogene rock

xenoliths in the carbonatites, as well as the fact that the latest phonolites are overlain by Middle Quaternary

sands.

The investigation showed that some of the rock-types of the Khanneshin volcanic complex contain high

concentrations of the elements commonly found in rare-earth carbonatites. These are phosphorus, iron, rare-

earths, barium, strontium, fluorine, niobium and lead. It was also found that commercial uranium ore was

produced by the post-volcanic activity.

The Khanneshin volcanic complex is composed mainly of carbonatites, which form a central-type volcanic

cone, and leucitic phonolites that are the products of fissure eruptions. The Khanneshin volcanic structure isnow an eroded volcano with a pronounced magma-conducting vent and relics of the tuff cone (Fig. 4). The

central part of the volcano is a soevite stock, about 3 km in diameter. The stock is surrounded by an ankerite-

barite carbonatite extrusion cutting the soevite and soevite-bearing xenoliths. The southern portion of the

volcano contains three stock-like bodies of fine-grained calcite carbonatite-alvikite, traceable along the

boundary between the soevite and ankerite-barite carbonatite. The bodies contact along faults; to the west

and north-west from the stocks, relics of alvikite lava-breccia flows are found, and to the east and south,

agglomerates of the same rocks can be observed. The old portions of the cone adjacent to the volcano consist

of brick-red, thick-bedded carbonatite tuff. Further outward, there are orange ash carbonatite tuff and tuffite,

a pronounced cross-bedding of which suggests a local redeposition of the material. The upper orange tuff

beds include interlayers of green-coloured inequiclastic carbonatite tuff and tuff-conglomerate containing

fragments and lapilli of soevite, alvikite, glimmerite, etc. At a distance of 3-10 km from the central volcano,

the tuff grades into unconsolidated tuffaceous cross-bedded sandstone, cut through by steeply-dippingcarbonatite dykes, 0.1 to 0.5 metres in thickness and more than 3 kilometres in length. To the south-east of

the volcano, there are small outcrops of leucitic phonolite, which are outliers of a thin lava flow. A stock-like

leucite phonolite body is associated with one of the outcrops.

Thus, the volcanic complex consists of the following lithologo-petrographic varieties (from early to late

ones): (1) carbonatite tuff and tuffite of the cone; (2) light-grey soevite of the central stock; (3) black

ankerite-barite carbonatite of the extrusive ring, and associated lahar breccias; (4) grey compact alvikite of

the minor extrusive stocks, lava-breccias of alvikite flows, thick-bedded tuff of the crater, and vent

agglomerates; (5) carbonatite dykes; (6) leucite phonolite.

Apart from the ferruginized carbonate material, the brick-red tuff and tuffite contain lithoclastic ankerite-

bearing soevite, crystalloclasts of carbonate, phlogopite, apatite and magnetite, and fragments of quartz,plagioclase, K-feldspar, microquartzite and siltstone. The prevailing medium-grained banded or spotted

soevite contains large endogenic inclusions of gigantic-grained soevite, biotitic and phlogopitic glimmerite


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and fenite. The medium grained soevite is of a blastoclastic texture, mainly consisting of the following

minerals: calcite and barite (0-7%), reddish-brown biotite (3-10%), occasionally fine-flaky

tetraferriphlogopite (0-10%), magnetite (3-5%), acmite (0-3%) and apatite (0-3%). Ankerite may be found

locally. Pyrochlore, zircon and barite are accessory minerals. The glimmerite inclusions in the soevite reach

several metres in diameter. These are of a biotite or phlogopite variety. Among the fenite inclusions, albite

and K-feldspar varieties may be distinguished. The former is a melanocratic fine-grained rock consisting of

albite (50-60%), amphibole (15-20%) and biotite (20-25%). It exhibits a porphyritic texture, with

arfvedsonite phenocrysts, which is also of a porphyritic texture containing phenocrysts of orthoclase andalkaline amphibole. The groundmass consists of isometric orthoclase grains, acicular acmite, alkaline

amphibole, apatite and calcite.

Calcite and ankerite are the dominant constituents in the black ankerite barite carbonatite. Barite (5-50%) is

found in aggregates of minute (0.1 mm.) idiomorphic crystals. Magnetite (5-25%) is martitized. fluorite (0-

15%) fills small nests (up to 0.5 mm. in size). Aegirite (0.2%) occurs as rosette aggregates of acicular

crystals. Phlogopite (0-5%) is fine-flaky, and galena is accessory. Glimmerite inclusions consist of

phlogopite-bearing varieties. The northern portion of the volcanic cone includes a mantle-like body of a

coarse breccia composed of soevite and ankerite-barite carbonatite fragments. Patches of flow layering and

local accumulations of large lumps may be observed locally. This evidence indicates that these formations

can be regarded as lahar ones.

The alvikite of the extrusive bodies is a compact fine-grained rock abundant in various inclusions. Under the

microscope, it exhibits a porphyritic texture. The phenocrysts are represented by calcite, monoclinic

pyroxene, biotite, garnet, apatite, melilite and magnetite. Most of the phenocrysts are of a relict nature,

bearing traces of the carbonatite melt. The carbonate groundmass of the rock is composed of fine-grained

calcite. The alvikite contains large xenoliths of early phase carbonatites and numerous nodules of silicate

rocks (garnetiferous and apatite-magnetite-pyroxene rocks), these made up of apatite (10-30%), magnetite

(5-40%) and monoclinic pyroxene (40-60%) with accessory carbonate, biotite, garnet and K-feldspar. The

garnetiferous rock consists of 60-80 per cent garnet, 10-40 per cent K-feldspar and small amounts of

monoclinic pyroxene, biotite, carbonate, magnetite and apatite. Garnet and feldspar are commonly

carbonatized.

The rocks composing the carbonatite dykes may be divided into two groups. The first group includesmassive alvikites similar to those mentioned above, and the second. dykes composed of porous calcitic

carbonatite, which contains magnetite, aegirite and thin-flaky chlorite-like mineral.

Leucitic phonolite has a porphyritic texture, the porphyric inclusions (50-70 per cent) consisting of leucite

crystals 0.2-0.5 mm in size. The groundmass is composed of xenomorphic sanidine, aegirite, nepheline and

carbonate.

Considerable amounts of apatite are present in all the carbonatite rock types, the largest being found in

alkivite (8.28 per cent). The apatite crystals vary in size from 0.1 to 5.0 mm or more. The mineral contains

0.4 per cent cerium, 0.08 per cent lanthanum, 0.5 per cent strontium, and 5.0 per cent barium. Thorium

mineralization is associated with the barite-ankerite calcite carbonatite of the ring extrusion, with the

carbonatite dykes and with the crush zones in Neogene red beds, where thorium-bearing carbonates areestablished, including berbankite and torbastnesite. These rocks are notable for their high concentrations of

rare earths of the lanthanum and cerium group (1-13 per cent). The pyrochlore found in the soevite of the

central stock and in the associated glimmerite forms idiomorphic transparent crystals, 0.2-0.5 mm in size,

containing calcium, iron, barium, strontium, tantalum, sodium, uranium, thorium, cerium, lanthanum and

vanadium. Barite and fluorite are important constituents of the ankerite carbonatite of the ring extrusion.

Strontianite is present in the early soevite and in the ankerite carbonatite (2-7%). Magnetite is commonly

intensely martitized, its content in the ankerite-barite carbonatite reaching 25 per cent.

The products of the post-volcanic hydrothermal activity of the Khanneshin volcano represent the Khanneshin

uranium deposit located in the south-west of the structure in Neogene terrigenous red beds [33, 80]. The red beds

are intruded by nine carbonatite dykes 5-50 cm thick, running for 300-1,500 metres along radial fractures. The

mineralization is confined to a steeply-dipping fault. The enclosing sandstone has undergone hydrothermal and

metasomatic transformations in the fault zone thus giving, rises to replacement of the primary iron-clay-carbonate

cement by dolomite-chlorite aggregate. Later, in the mineralization phase, uranium and uranium-bearing minerals


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precipitated along the vertical N-W-trending fractures. Four ore bodies are known from the deposit. One of them

is over 300 metres long and 14.2 to 58 metres thick. High uranium concentrations of sometimes more than 1 per

cent of the metal are found in the patches abundant in fractures in the course-grained sandstone. The ore stringers

2 mm to 1.5 cm thick are symmetrically handed. Their outer parts are composed of dolomite bearing 0.5 per cent

cerium, 0.4 per cent lantanum and 0.2 per cent barium. The cores consist of lamellar calcite aggregates, radial

barium ursilite crystals, uranyl silicates (vicoite and boltwoodite ), galena and reniform spherical metauksite

inclusions. In swells, the fractures often contain uranium-bearing chalcedony (hyalite) and aragonite. The

chemical composition, averaged for 10 ore samples, was as follows: 46.53% SiO2, 5.76% MgO, 2.67% Fe2O3,1.14% FeO, 5.78% Al2O3, 0.53% TiO2, 0.05% MnO; 1.63% P2O5, 1.95% SO3, 0.60% Na2O, 3.18% K2O, 0.47%

SrO, 0.34% BaO, 17.24% loss on ignition. The oxidised zone, up to 5-7 m thick, includes uranium silicates,

hydrouranate and uranyl phosphate, as well as uranium-bearing gypsum.

Some 80 kilometres south of the Khanneshin structure, there are several unique deposits of aragonite (onyx)

(Melek-Dokand, Zordag, Arbu and others). These are paragenetically associated with andesite-dacite volcanics

of Pleistocene age. The barium, strontium and rare earth determined in the analysed samples: collected from the

aragonite veins at the Zordag deposit [160] suggest that these veins are genetically related to the rocks of the

Khanneshin carbonatite complex. This means that the aragonite veins can be regarded as products of the

hydrothermal activity of the carbonatite chamber. The aragonite occurs at the Arbu deposit, either in a series of

sheet-like bodies localized around the andesite-dacite neck at the contact between the lavas and the enclosing

Neogene terrigeneous sediments, or in subconcordant bodies imbedded subhorizontally in the sedimentaryrocks. The main commercial aragonite accumulations within the Zordag deposit occur in the andesite-dacite

and at its contact with the Neogene sediments. The northern aragonite body, 30-45 metres thick, extends for

300 metres along the strike. It is composed essentially of aragonite of green shades, with inclusions of the

enclosing volcanic rocks. At the Malek-Dokand deposit, aragonite occurs 3-6 kilometres off the andesite-dacite

neck, either in Cretaceous volcanics or in Neogene sedimentary strata. The aragonite bodies occurring in the

volcanic rocks are large flat-lying sheets, lying parallel to each other. Aragonite was studied by V.I. Slavin

[142] and classified into the following morphological types: (a) fine-fibre mineral, forming rhythmical thin-

banded and micro-spherolitic aggregates; (b) spherolitic mineral forming symmetrically banded veins; (c)

coarse-crystalline mineral filling in open cavities in the veins. Aragonite shows a great variety in colour, with

predominating light to dark green varieties, The estimated reserves of the aragonite are two million tonnes.

Evidence of carbonatite activity has been established at the eastern margin of the South Afghanistan MedianMass, is the fields of the Dashte Nawer Early Quaternary volcanic series. There, a ten-metre horizon of

crystalloclastic trachyandesite-dacite tuff with up to 30 per cent in carbonate content was found to outcrop in

fragments within an area of a few dozen sq. km [155]. The pyroclastic fragments of trachy-andesite-dacite,

barkevikite, biotite and plagioclase immersed in the carbonate material show evidence of fusion. These rocks

reveal high concentrations of barium, strontium, rare earths and other elements commonly found in carbonatites.

The structural position, petrographic composition and geochemical characteristics of the rocks composing

the Khanneshin carbonatite complex have much in common with the carbonatite bodies known in other parts

of the world. A characteristic feature of the Khanneshin carbonatites is that they contain no silicate rocks.

Similar carbonatite complexes are known only in the Pufunda Region in East Africa.

Skarn Deposits

Various mineral deposits and occurrences of iron, copper, lead, zinc, tin, tungsten, etc. are associated with skarn

rocks in Afghanistan. Most of them are localized in carbonate rocks occurring at the exocontacts of intrusive

massifs of different ages. For example, the high concentrations of ore minerals found in skarn bodies are

associated with the Early Carboniferous gabbro-plagiogranite formation (iron, copper), the Early Triassic

granites of the batholithic formation, the subvolcanic granite formation (copper, lead, zinc and tungsten), the

Early Cretaceous gabbro-plagiogranite formation (iron), the Late Cretaceous-Paleocene gabbro monzonite-

syenite formation (gold, copper, lead, zinc, tin, tungsten and boron), the Oligocene granite batholith formation

(copper, gold, lead, zinc, tungsten, tin and bismuth), and the Miocene minor diorite porphyrite and syenite-

porphyry intrusions (gold, copper and iron). The ore minerals were formed either simultaneously with theskarn-forming silicates, or were introduced to the skarns during the hydrothermal stage. The skarn deposits and

occurrences known in Afghanistan can be subdivided into several skarn formations.


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Skarn magnetite formation

The deposits and occurrences of this formation are found in various structural-facies zones and were formed

in different metallogenetic epochs. The Baikalian epoch was responsible for the amphibole-magnetite skarns

(Duzukh Darah occurrence) found in the carbonate strata at the exocontacts of Proterozoic gabbro-diorite

massifs. The Hercynian metallogenetic epoch saw the formation of epidote-garnet-magnetite skarns, having

in places high copper concentrations [102]. Considerable amounts of magnetite skarn were formed during the

Meso-Cenozoic epoch of tectonic activation in the South Afghanistan Median Mass and Afghanistan-SouthPamir Folded Region. In the South Afghanistan Median Mass, magnetite skarns occur at the exocontacts of

Oligocene granitic rocks of the Argandab Complex. Typical of this formation is the Khwaja-Alam deposit,

consisting of lenticular bodies of rich magnetite ore occurring in Triassic dolomites. The ore minerals are

magnetite (90%), copper and iron sulphides. The iron content in the ore varies from 51.86 to 67.3 per cent.

There are over 20 occurrences and one iron ore deposit belonging to the magnetite formation (Furmoragh

deposit) in Afghanistan-South Pamir Folded Region. According to G.G. Semionov [133], the Furmoragh

deposit is a large body of massive magnetite ore assaying up to 55 per cent iron.

Formation of magnetite-hematite-chalcopyrite skarns

The occurrences of this formation are associated with Oligocene subvolcanic granite-granosyenite intrusions

(Bulghaja Complex), and with Miocene minor diorite porphyrite and syenite-porphyry intrusions (Share-

Arman Complex). The first group of occurrences is found in the west of the South Afghanistan Median Mass

(Sindand-Kiahmaran Zone), in Lower Cretaceous limestones. The pyroxene-garnet-vesuvianite skarns

widespread in the exocontact zones of the Bulghaja granite intrusions carry disseminated magnetite,

hematite, copper, lead and zinc sulphides (Korezak occurrence). The other group of occurrences is found in

the Murghab-Hari Rod Block of the North Afghan Platform, in the exocontact zones of Miocene diorite

porphyrite massifs which intrude the Cretaceous-Paleocene carbonate strata. The epidote-garnet, epidote-

garnet-magnetite and epidote-hematite skarns developed there contain disseminated inclusions, veinlets and

pockets of chalcopyrite, magnetite, hematite, galena, arsenopyrite, pyrite, covellite and chalcocite. The

skarn-type mineral deposits are irregular in shape and small in size (Okhankoshan occurrence, etc.). The

occurrences of this formation are of low economic values.

Skarn pyrite-chalcopyrite formation

The deposits and numerous occurrences of this formation are found only in the South Afghanistan Median

Mass and are confined mainly to the Tirin-Argandab Block in the Triassic terrigenous-carbonate strata, at the

contact with the intrusions of the Zarkashan and Argandab complexes. Pyrite-chalcopyrite mineralization is

associated with pyroxene, amphibole, garnet, pyroxene-garnet, phlogopite, phlogopite-pyroxene, phlogopite-

pyroxene-magnetite, and magnetite-pyroxene-garnet-phlogopite skarns. The largest concentrations of

sulphides occur in the phlogopite-magnetite and magnetite-pyroxene garnet-phlogopite skarns. In addition to

pyrite, chalcopyrite and magnetite, the skarns include sphalerite, molybdenite and tetrahedrite. Silver, gold

and bismuth and normal accessory constituents contained in skarn rocks of this type.

The Kundalan deposit consists of 13 lens-like skarn beds, up to 12.5 metres thick and 158 metres long. The

carbonate rocks forming roof sags are intruded by diorites of the Zarkashan Complex. The magnetite-

pyroxene-garnet-phlogopite skarns carry chalcopyrite, magnetite, pyrite, sphalerite, tetrahedrite, chalcocite,molybdenite, galena, enartite [enargite?], bornite, covellite, malachite, and native copper. Promising areas for

ore deposits of this formation are found in exocontact zones of Late Cretaceous-Paleocene and Oligocene

intrusions in the Argandab-Tirin Zone.

Skarn copper-lead-zinc formation

Occurrences of this formation are discovered within South Afghanistan Median Mass and in the Region of

Hercynian Folding. In South Afghanistan Median Mass, these are associated with the intrusions of the Late

Cretaceous-Paleocene gabbro-monzonite-syenite formation (Zarkashan Complex), with the Oligocene

granite batholith formation (Helmand and Argandab Complexes) and with subvolcanic granites (Balghaja

Complex). Copper, lead and zinc mineralization is associated with diopside-garnet, epidote-diopside-garnet

and diopside-tremolite skarns containing scapolite and vesuvianite. The ore minerals are represented bychalcopyrite, galena, sphalerite, pyrite and bornite. Skarn rocks occur in lenticular bodies varying from 0.5-3


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to several dozen metres in thickness and from 10-15 m to several hundred metres in length. The known ore

occurrences of this formation (Dalainor, Gariba, Morkokh and others) are of no economic value.

The occurrences of the copper-lead-zinc formation from the Region of Hercynian Folding (Darrah-Alasang,

Eshpushta and others) are situated in the exocontact zones of Late Triassic granitic rocks of the Murkh

Complex. The skarn lenses up to 30 metres thick and 200 metres long contain disseminated pyrrhotite,

chalcopyrite, sphalerite, galena, scheelite, cassiterite, ilmenite, pyrite, arsenopyrite and molybdenite. The

skarns have been found to contain 0.1-5.0 per cent copper, 0.01-1.0 per cent lead, and 0.01-3.0 per cent zinc.

Skarn lead-and-zinc formation

The formation includes the Bibi-Gaukhar deposit and a number of minor occurrences localized within the

Argandab-Tirin metallogenic zone, in the contact zones of Oligocene granitic rock massifs.

The Bibi-Gaukhar deposit is restricted to an inlier of the marmorized skarn limestone occurring in granites.

The main ore body is lens-like in shape; it is about 50 metres long and up to 10 metres thick. It is composed

primarily of sphalerite and galena (70-90%) with subordinate pyrite, garnet, augite and wollastonite. Base

metal mineralization can also be observed in garnet skarns, lead and zinc being either disseminated or

occurring in veinlets. In Zardgolak, Takmak and other areas, lead-and-zinc mineralization is localized in

small skarn bodies, 10 by 15 metres in size, occurring in carbonate rocks at their contact with Oligocene

granites. These are garnet and diopside-tremolite skarns mineralized by galena, chalcopyrite, magnetite,

pyrite and iron hydroxides.

Skarn copper-gold formation

The deposits and occurrences of this formation are distributed chiefly in the north-eastern part of the

Argandab-Tirin Zone of South Afghanistan Median Mass; (Zarkashan deposit and others). These are

associated with skarnified rocks and skarns occurring in Late Triassic dolomites in the exocontact zones of

the Zarkashan gabbro, monzonite and syenite massifs, and Argandab granitic rock massifs. The skarn rocks

occur in pockets or, occasionally, in sheet-like bodies. There are forsterite-diopside, spinel-phlogopite,

diopside, diopside-phlogopite, vesuvianite-diopside-phlogopite, phlogopite vesuvianite diopside, phlogopite-

diopside-vesuvianite, diopside-tremolite-vesuvianite, tremolite-garnet, diopside garnet, epidote-garnet and

garnet skarns. The ore minerals in skarns include magnetite, chalcopyrite, gold, pyrrhotite, pyrite, bornite

and chalcocite. At the Zarkashan deposit, gold is associated with copper sulphides, quartz, calcite and

serpentine. The richest gold-chalcopyrite ore is found in phlogopite skarns. The are bodies are not persistent

along the strikes and dips, the mineralization being extremely irregular. The gold content varies from

"traces" to 245 gr/tonne and that of copper, from 0.01 to 15 per cent. Lead, zinc, molybdenum and cadmium

occur in minor quantities.

Formation of tin-bearing skarns

The tin occurrences of this formation are known in the South Afghanistan Median Mass. Most of the tin-

bearing skarn zones occur in faulted limestones, within a certain distance from the contacts with granitic rock

massifs. These zones also carry iron, copper, lead, zinc, gold, molybdenum, tungsten, etc., which were

formed in the skarns of a later phase of mineralization. The tin mineralization process spans the period ofskarnization and later superimposed hydrothermal activity. According to their origin and mineral

assemblages, the skarn rocks can be classified into calcareous skarns with cassiterite, and magnesium skarns

with stannous borates. The cassiterite-ferrous carbonate skarns from the Argandab-Tirin Zone are tentatively

included in this formation. All three types of mineralization may occasionally be observed within the same

ore field. Calcareous skarns with cassiterite occur at the Chenar deposit, which is composed of Upper

Triassic dolomitized limestones intruded by Oligocene granodiorites, granosyenites and granites. The

sedimentary rocks, exhibiting a gentle monoclinal dip, are cut by a system of NE-and EW-trending faults.

The zones of calcareous skarns are restricted to the NE fending faults that extend from a few dozen to 1,150

metres. Large zones consist of lenticular bodies varying in thickness from 0.2 to 16 m, with 10-12 m on

average. The zone referred to as "Central" is represented by a dyke of silicified and skarnified dioritic

porphyrite carrying disseminated molybdenite, chalcopyrite and pyrite. Garnet-diopside skarns containing

vesuvianite, epidote, magnetite, chalcopyrite, bornite, molybdenite, ludwigite, phlogopite, cassiterite and

gold occur along the dyke and its extension.


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Formation of tungsten-bearing skarns

Tungsten-bearing skarns are known from the South Afghanistan Median Mass. These occur at contacts

between Proterozoic and Mesozoic terrigenous-carbonate rocks and Late Cretaceous-Paleocene gabbro-

monzonite-syenite intrusions (the Zarkashan and Farah Complexes) and Oligocene granite batholiths (the

Helmand and Argandab Complexes).

According to the type of tungsten mineralization, the skarns belong to the scheelite subtype. Ore occurrences

are known from South Afghanistan Median Mass in the Shindand-Kishmaran, Helmand and Argandab-Tirin

zones (the Kharnay, Baragana, Farah and other occurrences). The Kharnay occurrence localized in the

central portion of the Argandab-Tirin Zone is the largest of the thoroughly studied occurrences. The ore field

is underlain by Lower Silurian hornfelsed sandstones and siltstones containing inter-layered limestone

intruded by granites of the Argandab Complex. The skarns of amphibole-garnet-pyroxene and essentially

pyroxene composition are restricted to the NE-trending faults. There are several skarn zones in the area. The

largest zone extends for more than 2 kilometres at a width of 96 metres. It is intersected by transverse faults.

The faults running in the terrigenous rocks enclose fine-grained greisens or thin streaks of pyroxene material,

and those crossing the marble contain stringers and veins of pyroxene-amphibole skarns up to 10 cm thick

bearing wollastonite and rhodonite. Quartz-scheelite mineralization occurs along the axis of the skarn

stringers. Chalcopyrite, molybdenite and beryl may be found along with scheelite, which normally contains

0.11 to 0.22 per cent molybdenum. There are two distinct stages of skarn development at the Kharnayoccurrence. During the first stage, wide and extensive zones of barren skarnified rocks developed along the

NE-trending faults. In the second stage, skarn was formed along the NW-trending faults. The process was

accompanied by the deposition of ore minerals in places where the NW-trending faults intersect either the

marble layers or the garnet-amphibole-pyroxene skarns.

Skarn formation of gem and ornamental stones

This type of mineralization includes a group of ruby and lazurite deposits that has formed as a result of the

contact-metasomatic impact of ultra-acidic granitic rocks upon Precambrian carbonate rocks in the Nurestan-

Pamir Median Mass. The ruby occurrences are confined to a unit of calcite-dolomitic marble beds occurring

in Precambrian gneiss. The Jigdalek ore field includes two marble and calciphyre zones bearing rubies and

noble spinel and extending for 15 kilometres. The ruby crystals in the calciphyres are observed in the direct

proximity of pegmatite and migmatite veins. According to G.K. Yeriomenko, the rubies are associated with

phlogopite, Al-pargasite, forsterite, diopside, scapolite, chondrodite, spinel, pyrite, pyrrhotite, ilmenorutile

and nigerite. The ruby crystals are occasionally as large as 2.5 centimetres. The paragenesis of the rock-

forming minerals in the ruby bearing magnesium calciphyres is similar to that of the high-temperature

magnesium skarns. The post-magmatic solutions responsible for the ruby mineralization contained highly

active aluminium, while the activity of iron and alkali was rather low, as evidenced by the common

paragenesis of calcite + phlogopite Al-pargasite + corundum established in the calcyphyres. Also of interest

is the fact ore-forming fluids contained rare metals that have given rise to ilmenorutile, nigerite and beryl, as

well as boron and sulphur resulting in tourmaline, pyrite and pyrrhotite.

A group of unique lazurite deposits of Sare-Sang is located in the Southern Badakhshan Fault Block.

Lazurite deposits and occurrences have been found in the ares that extend for more than 200 sq. km and

underlain by biotite gneiss, calcitic and dolomitic marbles, forsterite and scapolite calciphyres, hornblende

and biotite-garnet schists, garnet amphibolite and skarns. The lazurite mineralization is confined to skarn

zones in calciphyres and is represented by lenses and pockets of lazurite-rich rocks composed of diopside,

forsterite, plagioclase, nepheline, sphene, scapolite, sodalite, pyrite, graphite and native sulphur [97].

Hydrothermal Deposits

Two types of hydrothermal deposits are known to occur in Afghanistan. These are plutonic and telethermal

deposits [145].

Plutonic ore formations include quartz-scheelite, quartz-gold-sulphide, quartz-sulphide, quartz-cassiterite,

wolframite-quartz, cassiterite-silicate, cassiterite-sulphide, copper-porphyry, talc-magnesite, quartz-ankerite-

beryl and chrysotile-asbestos deposits and occurrences.


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Quartz-scheelite formation

Occurrences of this ore formation are known from the South Afghanistan Median Mass and from the

Helmand and Argandab-Tirin Blocks, where they are spatially and paragenetically associated with Oligocene

granitic rocks (Nili, Wardak, Kakrak, Sangi-Mosha and other occurrences). The Nili occurrence is the most

typical and well-studied formation of this kind [146], consisting of several parallel stockwork zones found in

granites and extending for 1,700 metres, with widths of 30-50 metres. The scheelite-quartz veinlets vary in

thickness from 0.5 to 15 mm., their length reaching 50 metres. The scheelite occurring in the veinlets isdistributed irregularly. Grains of pyrite, chalcopyrite, bornite, cassiterite, bismuthinite, arsenopyrite and

wolframite are present in small quantities. The granite within the stockwork zones is silicified and

occasionally slightly greisenized. The tungsten content in the zones is low, not generally above 0.15 per cent.

Quartz-gold sulphide formation

This formation includes deposits and occurrences of quartz veins and crush zones bearing gold-sulphide

mineralization. Vein deposits are most frequent in Western Badakhshan (Chilkonshar, Shegnan, and others); In

the Argandab-Tirin Zone (Kandahar, Rishab and others) they are less common. Quartz veins occur in

metamorphic and terrigenous-carbonate rocks near intrusive massifs with ages ranging from Early Carboniferous

to Oligocene. The ore minerals found in the quartz veins are represented by gold, pyrite, chalcopyrite, sphalerite,

galena, hematite, arsenopyrite, and pyrrhotite. At the Chilkonshar deposit, the quartz veins are emplaced in Lower

Carboniferous basic volcanics and vary from 0.2 to 6.5 metres in thickness and from 20 to 300 metres in extent.

The gold content in some of the veins is between 12.3 to 84.9 gr/t. The quartz veins from the Argandab-Tirin

Zone occur in Eocene-Oligocene volcanic rocks. Quartz shows irregular disseminations of chalcopyrite, galena

and hematite. The gold content in the veins varies from traces to 10 gr/t. Silicified crush zones with gold-sulphide

mineralization are known to occur in Western Badakhshan in Proterozoic and Paleozoic rocks (Weka Dur

occurrence and others). The ore mineralization in the veins is of a dissemination type and consists of native gold,

chalcopyrite, galena and arsenopyrite; tetradymite and scheelite are also be found. There are many occurrences of

this type in the Argandab-Tirin Zone (Bala, Mirzaka, Dynamite, Kadalak, etc.). These are thick (up to 50 metres)

and extensive (up to 1 kilometre) silicified, limonitized and serpentinized crush zones localized in Mesozoic

carbonate-terrigenous rocks near granitic and basic rock massifs. For example, the zones of solidification,

serpentinization and sulphide mineralization from the Mirzaka occurrence are confined to carbonate-terrigenous

rocks intruded by sills and dykes of the Zarkashan gabbro-diorite complex. The ore bodies are composed ofstrongly ochreous brecciated silicified carbonate rocks containing magnetite, cerussite, pyromorphite, galena,

scheelite, cassiterite, arsenopyrite and wulfenite. The ore

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