Chapter 19A. Summary for the Dudkash Industrial Minerals 

Area of Interest

Contribution by Victor G. Mossotti, Barry C. Moring, Greta J. Orris, and Kathleen D. Gans

Abstract

This chapter summarizes and interprets the results from the study of the Dudkash industrial

minerals area of interest (AOI) and its subareas from joint geologic and compilation activities conducted 

from 2009 to 2011 by the U.S. Geological Survey, the U.S. Department of Defense Task Force for 

Business and Stability, and the Afghanistan Geological Survey. Accompanying complementary chapters 

19B and 19C address hyperspectral data and geohydrologic assessments, respectively, of the Dudkash

industrial minerals (gypsum) AOI. Additionally, supporting data and other information for this chapter 

are available from the Ministry of Mines, Kabul.

The Dudkash industrial minerals AOI is a rectangular expanse of mountainous and semi 

mountainous terrane covering 4,922 square kilometers overlapping the north and central Baghlan 

Province and intersecting the southeastern Kunduz and Takhar Provinces. The following districts are 

present in the AOI: Dahana-i-Ghori, Dushi, Pul-e Khumri, Nahrin, Baghlan, Burka, Baghlan-e Jadid, 

Khost Wa Firing, Ishkamish, and Aliabad districts. Industrial minerals of the AOI described in this 

report include cement-grade limestone, dolomite, celestite, gypsum, brick clay and coal.

The AOI is underlain by Upper Paleozoic and Lower Mesozoic sedimentary rocks that lie on the 

southeast and southwest parts of the area. These rocks are uncomformably overlain by Jurassic to 

Paleogene sedimentary rocks that contain evaporite, limestone, clay and coal deposits. These rocks are 

covered in large areas by Quaternary fill. Known deposits with measured reserves in the AOI include: 

Pul-e Khumri limestone and Tangi Murch celestite; Mined or prospected commodities within the AOI 

include gypsum, clay, dolomite-limestone, and coal. The potential economic value of these commodities 

is still undetermined.

19A.1 Introduction

Gypsum, limestone-dolomite, clay, celestite, and coal are minerals of potential economic 

significance in the Dudkash industrial minerals area of interest (AOI). The AOI is an elongated 

rectangular expanse of mountainous, semimountainous, and basin terrane covering 4,922 square 

kilometers (km2

Figure 19A–2 shows the AOI in the context of the neighborhood of provincial districts at a scale 

of 1:1,500,000 and locations of mineral occurrences. The following districts are present: Dahana-iGhori, Dushi, Pul-e Khumri, Nahrin, Baghlan, Burka, Baghlan-e Jadid, Khost Wa Firing in Baghlan 

Province, Aliabad in Kunduz Province, and Ishkamish in Takhar Province.

) with about 80 percent of the AOI overlapping Baghlan province to the southwest and 

the remainder extending into Kunduz province and Takhar province to the northeast. 

Figure 19A–1 shows the perimeter of the AOI on a map layer of generalized lithological ages at a scale 

of 1:8,000,000; the insert in figure 19A–1 represents the AOI at a nominal scale of 1:2,500,000. The 

Dudkash industrial minerals AOI is underlain by Upper Paleozoic and Lower Mesozoic sedimentary 

rocks in southeast and southwest parts of the area. These rocks are unconformably overlain by Jurassic 

to Paleogene sedimentary rocks that contain evaporite, limestone, and clay deposits. These rocks are 

covered in large areas by Quaternary fill. Coal is mined in Nahrin district in Jurassic rocks of the central 

North Afghan Platform.
1364 Summaries of Important Areas for Mineral Investment and Production Opportunities of Nonfuel Minerals in Afghanistan

Figure 19A–1. Index map showing generalized geologic rock age and location of the Dudkash industrial minerals 

(gypsum) area of interest. 

19A.2 Regional Geologic Setting

The Dudkash industrial minerals AOI lays along the southern boundary of the Afghan–Tajik 

basin which extends from southern Tajikistan onto the North Afghan Platform. In its deepest portions in 

Tajikistan, the basin contains more than 10 kilometers (km) of post-Jurassic sedimentary fill. 

Stratigraphic details are discussed in chapter 16A. The rocks filling the basin were detached above a 

Late Jurassic salt unit in Neogene time and deformed into a series of large-scale folds and thrusts. In the 

anticlinoria, Paleogene rocks are commonly exposed on or near the surface; the intervening synclinoria 

contain as much as several kilometers of Neogene and younger continental clastic deposits (Harben, 

2002). 

Marine conditions existed through most of the Paleogene in the combined Amu Darya and 

Afghan-Tajik Basin (Klett and others, 2006). During the late Paleogene, the collision of the Arabian, 

Iranian, and Hindustan continental plates into the Eurasian plate closed the Neotethys Ocean resulting in 

uplift, marine regression, and, finally, deposition of continental sediments by the end of the Paleogene. 

The Paleogene rocks conformably overlie Cretaceous rocks in northern Afghanistan. Structural 

movements of the Afghan-Tajik Basin during the basinal stage of development (Jurassic through 

Paleogene) are characteristic of block-type platform tectonics (Klett and others, 2006). Structural highs, 

such as the North Afghan High and smaller uplifts, experienced slower subsidence and occasional 

positive movements that resulted in local disconformities and the absence of parts of the sedimentary 

sequence (Ulmishek, 2004). 
Chapter 19A. Summary for the Dudkash Industrial Minerals Area of Interest 1365

Figure 19A–2. Map showing mineral occurrences and the location of the Dudkash industrial minerals (gypsum) 

area of interest within the neighborhood of provincial districts at a scale of 1:1,500,000.

19A.3 Limestone-Dolomite

19A.3.1 Deposit Type

For the purposes of this assessment, limestone is defined as a carbonate rock containing greater 

than 50 percent calcite and (or) dolomite, with calcite predominating. Dolomite (CaMg(CO3)2 is also a 

carbonate rock and a mineral, both comprising calcium magnesium carbonate. Dolomite rock (also
1366 Summaries of Important Areas for Mineral Investment and Production Opportunities of Nonfuel Minerals in Afghanistan

known as dolostone) is composed predominantly of the mineral dolomite. Limestone that is partially 

replaced by dolomite is referred to as dolomitic limestone (Tucker and Wright, 1990). Siderite (FeCO3), 

rhodochrosite (MnCO3), calcite (CaCO3), and antigorite (Mg,Fe2+)3(Si2O5)(OH)4 commonly form 

epitaxal relationships with dolomite. Dolostone or marble are not differentiated among carbonate rock 

on the geologic maps prepared for this report, and hence are assumed to be locally present within the 

limestone units. 

19A.3.2 Probable Age(s) of Mineralization

Limestone deposits can be of any age, from Precambrian to Recent.

19A.3.3 Importance and Economic Expectation of Deposits

Limestone, the most important component in cement, is an extremely versatile commodity that is 

typically available at a low cost. The value of industrial grade limestone is associated with the chemistry 

of the rock. Ground calcium carbonate is used as filler in a variety of commodities from paper to 

pharmaceuticals, coatings, fertilizers, and other products. Among other applications, lime (CaO) is 

consumed for environmental uses such as wastewater treatment and flue gas desulfurization, as a soil 

treatment, in the production of steel and iron and other metals, in the production of chemicals, and in 

sugar refining (Harben, 2002; Oates, 1998, Freas and others, 2006). The value of dimension grade 

limestone is associated with the physical properties of the rock. Dimension stone is used for its strength, 

resistance to staining and weathering, and an aesthetic appeal. The demand for limestone normally 

increases with increasing gross domestic product (GDP). Most limestone quarries are small-scale and 

provide building stone for local markets; larger operations use standard open-pit mining methods.

19A.3.4 Descriptive Genetic Model

Most limestone of economic importance was deposited in a relatively shallow marine 

environment from a variable mix of biogenic, and to a lesser degree, chemical and mechanical processes 

(Oates, 1998; Freas and others, 2006). Limestones that were deposited in relatively high-energy 

depositional environments tend to contain less non-carbonate material and thus be higher grade (Freas 

and others, 2006). Deposits are commonly large and spatially extensive. Sedimentary sequences that 

contain limestone may also have dolomite, siltstone, and shale. Minor variations in depositional 

processes and conditions can lead to heterogeneity in CaCO3 grade, susceptibility to weathering, trace 

element content, and other factors that may negatively impact suitability of the limestone for 

development. Some sedimentary limestone deposits are of continental origin and can also be quite 

extensive. Carbonate rocks are susceptible to post-depositional alteration that may affect the CaCO3

content, trace element content or physical characteristics. These processes may enhance or detract from 

the suitability of the deposits for development. Some of these processes may lead to the formation of 

sulfide minerals, which can limit the use of the limestone for environmental reasons. Scholle and others 

(1983) provide a comprehensive overview of carbonate depositional environments. 

19A.3.5 Grade and Tonnage Model

Available information is insufficient to allow a quantitative assessment.

19A.3.6 Exploration History

Soviet and Afghan geologists identified a number of limestone deposits during geological 

surveys in the 1970s, but very little is known about exploration specifically for limestone deposits, 

especially information pertaining to quality and potential application of limestone resources. 

19A.3.7 Known Occurrences and Example Deposits

Limestone occurrences are widespread in Afghanistan. The Early Carboniferous Sabz deposit in 

Badakhshan Province has speculative limestone resources of about 500 million metric tons 

(United Nations Economic and Social Commission for Asia and the Pacific, 1995). The Early Triassic 
Chapter 19A. Summary for the Dudkash Industrial Minerals Area of Interest 1367

Darra-i-Chartagh (34°26'20"N; 62°46'00"E) deposit in Herat Province is more than 5 km long, more 

than 200 m thick, and is suitable for cement production. The Middle Triassic limestone at the 

Rod-i-Sanjur (34°26'N; 62°44'E) deposit in Herat Province is as much as 400 m thick (United Nations 

Economic and Social Commission for Asia and the Pacific, 1995). Other occurrences are located at the 

Bakunvij quarries in Badakhshan (United Nations Economic and Social Commission for Asia and the 

Pacific, 1995). 

19A.3.8 Tract Delineation and Boundary Criteria

Figure 19A–3 shows permissive tracts lms01 and lms02 (Doebrich and Wahl, 2006; Ludington 

and others, 2007) for limestone and marble with selected deposits and prospects within Dudkash AOI 

and surrounding area. The main limestone permissive tract (lms01) was delineated using the digital 

geologic map of Afghanistan (Doebrich and Wahl, 2006; Ludington and others, 2007). The tract consists 

of map units that have limestone or marble identified as a major or dominant component. Although 

limestone of different ages may well have different economic potential, limestone of all ages was 

combined for the delineation of tract lms01 because of lack information to develop criteria for 

establishing differing probabilities of occurrence in rocks of different ages. 

19A.3.9 Deposits and Prospects

The following limestone-dolomite deposits are present in the Dudkash industrial minerals AOI. 

19A.3.9.1 Pul-e Khumri Limestone, Baghlan Province (35°58'24"N, 68°40'56"E)

Upper Cretaceous–Paleocene 300- to 500-m-thick limestone occurs over an area of several 

thousand square kilometers. The rock is light colored, thick-bedded, and fine-crystalline. A large 

limestone deposit located close to Pul-e Khumri has been a readily available resource of raw material for 

the Ghori-I cement plant. The deposit consists of Danian (Paleocene) limestone beds, 300 to 400 m 

thick, exposed in the area of several thousand square kilometers. The limestone is pure, containing 52 to 

53 percent lime, 0.8 to 1.3 weight percent (wt. %) MgO, and 1.3 wt. % insoluble residue. 

19A.3.9.2 Dudkash Limestone, Baghlan Province (36°00'40"N, 69°46'00"E)

A 30-m-thick limestone bed crops out in between Jurassic clays and siltstones. The limestone is 

grey, stratified, compact, and aphanitic. To be used for cement production, it would need additional 

other agents. 

19A.3.9.3 Dudkash Dolomite, Baghlan Province (36°00'47"N, 68°47'20"E)

A 3.9-m-thick dolomite bed occurs in Lower Cretaceous siltstone, limestone, and gypsum units. 

In composition the rock is almost chemically pure dolomite.

19A.3.9.4 Shine Oghor Mine (Shenivaghur Mine), Dahana-i-Ghori District, Baghlan Province 

(35°43'47"N, 68°33'0"E)

A massive, kilometer-long and 80-m-thick black dolomite bed has been mined for some time 

(Mindat, 2011). 

19A.3.10 Optimistic Factors

Limited information about limestone quality indicates high (more than 90 percent) values of 

CaCO3 in limestone of varying ages. Limestone is widespread and occurs in large masses that could 

host large deposits. Some limestone has been metamorphosed, which can improve the quality for some 

uses.

19A.3.11 Pessimistic Factors

There is almost no information about quality or consistency of quality of limestone of any age.
1368 Summaries of Important Areas for Mineral Investment and Production Opportunities of Nonfuel Minerals in Afghanistan

19A.3.12 Important Data Sources

The main sources for information on limestone resources in Afghanistan include United Nations 

Economic and Social Commission for Asia and the Pacific (1995), Abdullah and others (1997), and

Doebrich and Wahl (2006). 

19A.4 Gypsum

19A.4.1 Probable Age(s) of Mineralization

Late Cretaceous to Neogene.

19A.4.2 Importance and Economic Expectation

Gypsum is a key component of wallboard, a cost-effective building material, and has additional 

uses in cement and agriculture. Gypsum demand increases with an expanding national GDP. Most of the 

currently active gypsum quarries are mined on a small scale and the utilization of the mined material is 

not specified in the literature.

Figure 19A–3. Map showing limestone and marble permissive tracts (lms01, lms02) with selected deposits and 

prospects (triangles) in Dudkash AOI, where blue, tract lms01 limestone, major component; olive green, tract 

lms02, industrial limestone, minor component; light green: marble.

19A.4.3 Descriptive Genetic Model

Gypsum and anhydrite are usually deposited in evaporitic sedimentary environments, peripheral 

to halite and bittern deposition (bromides, magnesium, calcium), if present. Gypsum deposits of both 

marine and continental origin are present in Afghanistan. Figure 19A–4 shows the permissive tract
Chapter 19A. Summary for the Dudkash Industrial Minerals Area of Interest 1369

(AFGy-01, from Doebrich and Wahl, 2006) for the occurrence of gypsum and anhydrite in the AOI and 

nearby regions, with locations of known major occurrences. 

19A.4.4 Grade and Tonnage Model

Available information is insufficient to allow a quantitative assessment.

19A.4.5 Exploration History

Largely unknown, although the Soviets and Afghans conducted geological surveys in the 1960s 

and early 1970s that made note of some of the deposits reported here. Supporting geologic studies of 

mineralized systems and assessment areas is available at the USGS Afghanistan website 

(http://afghanistan.cr.usgs.gov/ and at the Afghanistan Geological Survey website 

(http://www.bgs.ac.uk/afghanminerals/).

Figure 19A–4. Area considered permissive for the occurrence of gypsum and anhydrite with locations of known 

major occurrences (Tract AFGy-01) (From Doebrich and Wahl, 2006).
1370 Summaries of Important Areas for Mineral Investment and Production Opportunities of Nonfuel Minerals in Afghanistan

19A.4.6 Known Occurrences and Example Deposits

Gypsum deposits in the Dudkash industrial minerals AOI have been identified in Baghlan 

Province with exposures of Late Jurassic, Late Cretaceous to Paleocene, and less commonly, Neogene 

ages. Figure 19A–4 maps mixed permissive tracts for gypsum-bearing rock in the Dudkash AOI and 

surroundings. Examples of additional deposits far beyond the perimeter of the Dudkash AOI include the 

Sary-Asya deposit in Samangan Province and the Neogene Surkh-Rod deposit in Nangarhar Province. 

19A.4.5 Deposits and Prospects

The gypsum deposits present in the Dudkash industrial minerals AOI including the following: 

19A.4.5.1 Shoraw, Baghlan Province (36°03'45"N, 69°08'56"E)

A 1-m-thick gypsum bed occurs in Jurassic sandstone, clay and gritstone. The occurrence is 

being worked manually. 

19A.4.5.2 Dudkash Gypsum, Baghlan Province (36°00'55"N, 68°47'30"E)

Note that the name of the Dudkash industrial minerals AOI is taken from the name of this mine. 

The occurrence comprises massive 1.5- to as much as 6-m-thick gypsum beds, which occasionally 

extend for 12 km in Upper Jurassic clay, siltstone, sandstone, and dolomite. The gypsum has been 

mined. 

19A.4.6 Optimistic Factors

Some of the deposits are many thousands of meters long and 5 to more than 30 m thick. The few 

reported grades range from 89 percent to greater than 99 percent gypsum. Tracts are large in area and 

would readily host large deposits if present. 

19A.4.7 Pessimistic Factors

Very little data have been reported on gypsum quality; there is no information available on the 

consistency of the gypsum in terms of chemical or physical characteristics across the outcrop areas of 

gypsum of any given age. 

19A.4.8 Tract Delineation and Boundary Criteria

The gypsum tract shown in figure 19A–4 was delineated using outcrops of sedimentary units 

where gypsum was listed as a major or dominant component. Although it is likely that gypsum-bearing 

rocks of different ages have different potential, we lumped all ages due to an equal lack of distinguishing 

geologic information other than age. Areas of less promise consist of geologic units in which gypsum is 

listed as a minor component (area in bright blue in figure 19A–6). 

19A.4.9 Important Data Sources

Oil and gas assessment data; known salt occurrences (Klett and others, 2006). 

19A.5 Clay

All clays are a mix of fine-grained minerals with microscopic crystals of phyllosilicate minerals 

and with lesser amounts of organic material. These components collectively impart plasticity to wet clay 

and cause clay to harden when dried or fired in a kiln. There are three or four main groups of clays, the 

number depending on the reference source, with approximately 30 different types of pure clays in these 

categories. The three categories of clays considered by the USGS-AGS Assessment Team were adobebrick clay, refractory clay and porcelain clay (Ludington and others, 2007). Refractory clay (also known 

as fire clay) melts around 1,600°C (Theng, 1979). Refractory clay is used to line pouring spouts or entire 

furnaces for molten iron and steel, and with proper selection it can be used in kilns for cement 

production, to fire bricks and to contain molten glass without contaminating the glassy flux (Theng, 
Chapter 19A. Summary for the Dudkash Industrial Minerals Area of Interest 1371

1979). Porcelain clay is selected for a multiplicity of products because it turns glassy at elevated 

temperature, and adobe-brick clay is used for construction, but may swell and fall apart at elevated 

temperatures.

19A.5.1 Importance and Economic Expectation

Kaolin is used in ceramics, medicine, coated paper, as a food additive, in toothpaste, as a light 

diffusing material in white incandescent light bulbs, and in cosmetics. It is generally the main 

component in porcelain. It is also used in paint to extend titanium dioxide (TiO2) and modify gloss 

levels, and in rubber and adhesives to modify rheology. Bentonite is used for drilling muds because of 

its rheological properties. Bentonite subclasses are also used in ceramics.

19A.5.2 Mineralization

The dominant clay species are montmorillonite, bentonite, illite, and kaolinite. Montmorillonite 

is the main constituent of bentonite. For industrial purposes, two main classes of bentonite exist: sodium 

bentonite and calcium bentonite; a minor class, potassium bentonite is commonly referred to as illite. 

Kaolinite is a clay mineral with the chemical composition Al2Si2O5(OH)4 (Deer and others, 1992). 

Montmorillonite is the main constituent of bentonite. Bentonite usually forms from weathering of 

volcanic ash.

19A.5.3 Descriptive Genetic Model

Clay minerals are typically formed over long periods of time by the gradual chemical weathering 

of rocks, usually silicate-bearing, by low concentrations of carbonic acid (Velde, 1995). These solvents, 

usually acidic, migrate through the weathering rock after leaching through upper weathered layers. Clay 

minerals form from preexisting minerals where rocks are in contact with water, air, or steam (Klett and 

others, 2006). As such, environments for clay production are ubiquitous, including soil horizons, 

continental and marine sediments, geothermal fields, volcanic deposits, weathering rock formations, in 

sediments at the bottom of lakes or seas, and rocks in contact with water heated by magma 

(hydrothermal fluids). Clay deposits are typically associated with very low energy depositional 

environments such as large lakes and marine deposits in Mesozoic and Cenozoic strata. 

Clay deposits may be formed in place as residual deposits in soil, but thick deposits usually are 

formed as the result of a secondary sedimentary deposition process after they have been eroded and 

transported from their original location of formation. Primary clays, also known as kaolins, are located 

at the site of formation; secondary clay deposits have been moved by erosion and water from their 

primary location. Kaolinite occurs in abundance in soils that have formed from the chemical weathering 

of rocks in hot, moist climates; kaolinite typically occurs as a primary deposit. Rocks that are rich in 

kaolinite are known as white clay. Kaolinite-dominated clays are typically associated with coal.

19A.5.4 Grade and Tonnage Model and Economic Expectation

Available information is insufficient to allow a quantitative assessment.

19A.5.5 Exploration History

Soviet and Afghan geologists identified a number of limestone deposits during geological 

surveys in the 1970s, but very little is known about exploration specifically for limestone deposits, 

especially information pertaining to quality and potential application of limestone resources. 

19A.5.6 Known Occurrences and Example Deposits

Brick and refractory clays are present in the west in Herat Province, in the central parts of the 

country in Samanghan and Baghlan Provinces, and in Kabul Province. The clays occur mainly in Upper 

Jurassic and in Cenozoic clay-rich sedimentary rocks. Herat Province contains the Karukh and Malumat 

brick and fire-clay occurrences within calcareous silty and sandy material in Quaternary sedimentary 

formations. Delineation of the permissive area was guided by the occurrences of clay occurrences in the 
1372 Summaries of Important Areas for Mineral Investment and Production Opportunities of Nonfuel Minerals in Afghanistan

Loghar Valley, Loghar Province. In Samanghan and Baghlan Provinces the, coal-bearing Jurassic units 

contain sedimentary kaolin in unspecified map unit J12ssl. Clay occurrences include Rafak in the Ruyi 

Du Ab District within Lower Cretaceous siltstone that consists of a green to gray, 5-m-thick clay bed. 

The Nalak occurrence, in Upper Triassic weathered diorite porphyry, is a tabular deposit about 13 m 

thick consisting of gray, laminated clay. The Talin occurrence is hosted in Lower to Middle Jurassic 

rocks and contains five clay beds, 500 m long and 0.5 to 2.7 m thick. Speculative resources are 

385,000 metric tons (t) of clay (Abdullah and others, 1977). 

19A.5.7 Deposits and Prospects

The hyperspectral (2-millimeter) image of an area overlapping Pul-e Khumri and Nahrin districts 

in the Dudkash AOI shown in figure 19A–5 reveals the spatial distribution of kaolinite (Hillside blue). 

The Dahan-e Tor occurrence (35°43'13"N, 67°15'41"E), Dara-i Suf, Bala District, Samangan 

Province, is in Lower to Middle Jurassic clay-rich sedimentary sequences and is blue-gray, 40 to 50 m 

thick, and suitable for manufacturing of brick and roof tile. The Shabashak occurrence (34°41'36"N, 

67°27'0"E), Bamiyan district, Bamiyan province, is alkaline and suitable for drilling mud and as 

moulding clay. Cenozoic sedimentary rocks also contain clay-rich deposits. The Deh-Kapal occurrence

in Kabul Province (34°37'00"N; 66°04'30"E consists of Quaternary clays grading 5.63 percent silica and 

5.04 wt. percent hematite. Speculative resources of clay suitable for the ceramic industry are about 

2,200,000 m3 to a depth of 5 m. The Surkhab and Kaukpar occurrences in Pul-e Khumri and Nahrin 

districts, Baghlan Province, are hosted within sedimentary bentonite units of Neogene sandstone and 

conglomerate beds (Abdullah and others, 1977). 

19A.5.7.1 Surkhab Clay, Baghlan Province, 25°58'25"N, 68°40'32"E

Hosted within sedimentary bentonite units of Neogene sandstone and conglomerate beds 

(Abdullah and others, 1977). A bed of Neogene clay is used as an additive in cement production. 

19A.5.7.2 Kawkpar Clay, Baghlan Province, 35°56'55"N, 68°52'36"E

Clay 2- to 17-m-thick beds have been found between Neogene sandstone and conglomerate beds. 

The clay is lumpy, slightly gypsiferous.

19A.5.8 Optimistic Factors

Afghanistan contains abundant clays, with quantities sufficient to meet the demands of domestic 

construction where the application is relatively insensitive to the type of clay used. With the exception 

of the kaolins associated with the coals, little information is available about the composition of the clays. 

Further investigation into the type and composition of the clays would be necessary to determine where 

efforts should be put into developing them for other specialized uses. 

19A.6 Celestite

19A.6.1 Mineralization

Sedimentary celestite (SrSO4) deposits are the main source of celestite production. The 

strontium to form these deposits is variously believed to be sourced from marine-derived brines, from 

fluids resulting from the conversion of aragonite to calcite or gypsum to anhydrite, from waters formed 

by dolomitization of limestone, from dissolution of subsurface gypsum, and from basinal waters that 

have leached strontium from associated rocks (Warren, 1999; Hanor, 2000). In the area of Afghanistan 

represented by the Dudkash AOI, celestite mineralization is typically spatially associated with coal and 

petroleum (Abdullah and others, 1977). The two celestite deposits known in Afghanistan are reported to 

be Paleogene in age (Abdullah and others, 1977). Since the known deposits in Iran are also Paleogene, 

specifically Oligocene, in age, it is believed that any undiscovered deposits will also be found in 

sediments of that age.
Chapter 19A. Summary for the Dudkash Industrial Minerals Area of Interest 1373

Figure 19A–5. Hyperspectral image of an area overlapping Pul-e Khumri and Nahrin districts: Hillside Blue, 

kaolinite. From Hubbard, chapter 19B of this report.
1374 Summaries of Important Areas for Mineral Investment and Production Opportunities of Nonfuel Minerals in Afghanistan

Figure 19A–6. Location of important celestite deposits in the Dudkash AOI (Doebrich and Wahl, 2006).

19A.6.2 Importance and Economic Expectation

Sedimentary celestite deposits are the main source of celestite production. Celestite (SrSO4) is 

currently the dominant, if not the sole commercial source of strontium. More than 75 percent of the 

production of celestite is used in the production of radiation-absorbent glass for television, computer, 

sonar, and other screens (Harben, 2002). Half of the world’s annual production of just over 300,000 t is 

sourced from Mexico; most of the remaining production is from Spain (Harben and Kuzvart, 1996). The 

single most significant celestite deposit in Afghanistan is in Baghlan Province at Tangi Murch.

19A.6.3 Descriptive Genetic Model

The known deposits in Afghanistan and Iran contain characteristics similar to the bedded 

celestite type (Model 35a.1, Orris, 1992). Sedimentary celestite deposits can form in a variety of ways 

including primary precipitation, and through diagenetic and alteration processes. Celestite is commonly 
Chapter 19A. Summary for the Dudkash Industrial Minerals Area of Interest 1375

associated with evaporate deposits, as well as limestone and dolomite. In the Dudkash AOI, celestite 

(SrSO4) deposits of potential economic significance are hosted by layered limestone and gypsiferous 

clays of the Paleocene Bukhara and Suzak Formations. 

19A.6.4 Exploration History

In the mid-1970s, the Russians explored the Baghlan and Kunduz Provinces, reporting celestite 

deposits using multiple shallow drill holes, pits, and trenches. More than 80 samples were taken from 

the bituminous limestone-gypsum-celestite horizon of the Paleocene Bukhara Formation. Two deposits 

were estimated by the Russian workers to contain together more than 1 million metric tons (Mt) of 

celestite ore. It is probable that large celestite deposits, similar to those in Pakistan and Iran, occur in 

Afghanistan. Targeted exploration would probably reveal additional deposits (Harben, 2002). 

19A.6.5 Known Occurrences and Example Deposits

Preeminent celestite deposits are the Early Cretaceous deposits of Coahuila, Mexico, where they 

are found around the periphery of the Coahuila Platform (Rodriguez Garza and McAnulty, 1996). A 

major celestite deposit in the Dasht-e Kavir desert of Iran occurs in the lower part of the Oligocene Qum 

(Qom) Formation and is exposed in a northwest-trending ridge system. At the Nakhjir-kuh celestite 

deposit (Varamin, South Tehran, Iran, a 2- to 4-m-thick seam of celestite is mined by open-pit; more 

than 1 Mt of celestite is reported to be present at the nearby Talheh deposit (Harbena and Kuzvart, 

1996). Small amounts of celestite production have also been reported in Pakistan. 

19A.6.6 Known Prospects in Afghanistan

Abdullah and others, 1977, report two celestite deposits in Afghanistan: Kartaw and Tangi 

Murch. 

19A.6.6.1 Kartaw Deposit, Chahar Dara District, Kunduz Province: 36°42'N, 68°35'E

(This deposit is outside the Dudkash AOI.) The celestite forms a bed 1,400 m along strike that 

extends 10 to 14 m down dip and averages 0.9 m in thickness. Speculative resources of 1 Mt of white to 

bluish crystalline celestite were estimated.

19A.6.6.2 Tangi Murch, Burka District, Baghlan Province: 36°16'13"N, 69°12'24"E

(This deposit is within the Dudkash AOI.) This celestite deposit is a bedded occurrence hosted 

by Paleogene bituminous limestone and other sedimentary rocks of the Bukhara and Suzak Formations 

(Kasak and others, 1965; Orris and Bliss, 2002). The ore beds consist of fine to coarse-crystalline 

celestite-bearing rock. Four celestite ore beds have been located, their thicknesses ranging from 0.4 to 

1.67 m and over a maximal length of 170 m. The celestite content is from 29 to 77 vol. percent and the 

specific gravity, from 3.00 to 3.94 grams per cubic centimeter (g/cm3

). The speculative reserve of the 

celestite ore is 85,600 t, the average celestite content of 54 vol. percent and specific gravity of 3.43 

g/cm3. Statistics on the number of samples, reproducibility of the analytical results, or spatial sampling 

technique were not available. It is probable that large celestite deposits, similar to those in Pakistan and 

Iran, occur in Afghanistan. Targeted exploration would probably reveal additional deposits. 

19A.6.7 Tract Boundary Criteria

A permissive tract was delineated using the digital geologic map of Afghanistan (Doebrich and 

Wahl, 2006). The tract area consists of those map units that have evaporite deposits identified as a major 

or dominant component. Evaporite-bearing rocks of all ages were combined in this tract because we 

lacked information to develop criteria for differing probabilities of occurrence in rocks of different ages. 

Gypsum-anhydrite-bearing sediments of Late Cretaceous to Paleogene age were selected as proxies for 

celestite and then buffered five km outward because of the uncertainty of map unit boundaries due to 

near-horizontal stratigraphy (Orris and Bliss, 2002). Units in which limestone is a minor component in 
1376 Summaries of Important Areas for Mineral Investment and Production Opportunities of Nonfuel Minerals in Afghanistan

this area could be considered to have lower potential. Additional areas of interest were noted proximal to 

the known occurrences.

19A.7 Coal

Mineralization coal is formed by geological processes requiring a setting of elevated pressure 

and temperature over an extended period acting on buried detrital biotic material. The process begins 

with layers of plant matter accumulating in an anoxic environment, usually on the muddy bottom of a 

body of water. Over time, the chemical and physical properties of the vegetative remains are changed 

into a solid material that is mainly composed of carbon along with variable quantities of other elements, 

chiefly hydrogen, with smaller quantities of sulfur, oxygen and nitrogen. The harder forms of coal, such 

as anthracite, can be regarded as metamorphic rock because of longer exposure to elevated temperature 

and pressure. In general, the deeper the coal is buried, the higher the grade (rank) (Jones, 1949). of the 

coal. Moreover, deep coal deposits are considered prospectively valuable for coal-bed methane (CBM). 

The general quality of Afghan coals appears to vary considerably, both stratigraphically and laterally

(SanFilipo, 2005).

Most of the coal being mined in Afghanistan occurs in Jurassic rocks of the Northern Afghan 

platform. While this coal is of relatively high rank and grade, it is far from most major population 

centers, and can only be delivered by truck over primitive roads that cross difficult terrain. Paleogene 

coal also occurs in Afghanistan, but is generally restricted to the Katawaz Basin and associated areas of 

eastern Afghanistan. The Mesozoic and Paleogene coal basins are separated by continental-scale faults 

that mark current and ancient tectonic plate boundaries. The less mature Tertiary-age coals are typically 

high-ash and of low heating value. The shallower coal areas could have commercial potential for 

underground mining, CBM, and to a limited extent, surface mining.

19A.7.1 Importance and Economic Expectation

Coal utilization in Afghanistan has historically been restricted to households and small industry 

(notably in the manufacturing of cement and textiles, and in food processing). The main demand for coal 

is for brick making. A significant demand also exists for cooking and domestic heating during the winter 

season. Lack of transportation is the main factor limiting more widespread use of coal. The main factors 

limiting the widespread use of coal appear to be its limited availability, a consequence of inadequate 

mineral exploration, poor extraction infrastructure and transport problems.

Although Afghanistan produced more than 100,000 t of coal annually as late as the early 1990s, 

the country was producing only around 4,000 t as of 1998. Currently about 20 percent of coal production 

is from government owned mines operated by the Northern Coal Department (NCD) of the Afghan 

Ministry of Mines and Industry (MMI), or by associated agencies in Herat Province (Clough, 2007). The 

remainder of the production comes from small private artisanal mines. NCD mines have fallen into 

nearly total disrepair during the past 30 years, and all existing coal mines use obsolete extraction 

methods and inferior infrastructure for worker safety. The MMI estimates an increased in annual 

demand for coal to several million metric tons from the present level of 0.5 Mt in order to support the 

needs of new cement, brick and iron factories.

19A.7.2 Exploration History

Coal occurrences in Afghanistan were reported in Afghanistan starting with Griesbach (1881, 

1885, 1887a, 1887b) 130 years ago. Exploration continued into the twentieth century with Hayden 

(1911), West (1942) and others. Over the period 1963–1965, Soviet geologists and others carried out a 

geological survey on a scale of 1:200,000 in Northern Afghanistan (K.Ya. Mikhailov, V.P. Kolchanov, 

V.V. Kulakov, B.P. Pashkov). As a result of the survey the area of coal-bearing formations was studied 

and the North Afghanistan Coal Basin was recognized. There are nine coal fields and about 42 coal 

deposits in Afghanistan (Votrubec, 1982; Harben, 2002), most of which are found in the north of the 

country and all of which have been surveyed by the former Soviet Union. Coal resources in Balkhab, 
Chapter 19A. Summary for the Dudkash Industrial Minerals Area of Interest 1377

Samangan Province have recently been assessed by remote sensing sponsored by USAID (Sabins and 

Ellis, 2010). Two deposits were described in the report and designated as Balkhab East and Balkhab 

West (Sar-e Pol Province). 

19A.7.3 Known Occurrences and Example Deposits

Of the 40 coal deposits in Afghanistan, there are 11 coal mines with a history of production, and 

only 1 to 5 believed to be marginally viable for local production (Addison, 2007). Reserves associated 

with these deposits are listed as 98 Mt of coal (all quantitative estimations should be regarded as subject 

to refinement). Chapter 16A provides an overview of coal occurrences in Afghanistan on a regional 

scale. Apart from the Karkar and Dudkash coal mines near Pul-e Khumri in Baghlan (Afghan Chamber 

of Commerce, 2011), detailed information on actual production activities has been elusive. Coal 

occurrences of note in Afghanistan include: 

19A.7.3.1 Ishpushta Deposit, Baghlan Province 

Reserves are estimated to be 2.5 Mt of coal with a calorific value less than 20.90 megajoules per 

kilogram (MJ/kg). 

19A.7.3.2 Dara-i Suf Deposit, South of Mazar-i-Sharif, Samangan Provine 

Reserves of the Dara-i Suf basin in 8 to 40-m-thick coal seams with 10 to 35 percent ash content 

and 23.10 MJ/kg calorific value are estimated to be 50 Mt. 

19A.7.3.3 Gora Zabzak Deposit, Daykundi Province 

The deposit contains 12 seams of coal with 16.74 MJ/kg calorific value and 73.77 Mt of reserves 

(20.7 Mt of proved and mineable coal, 23.7 Mt of probably coal and 29.3 Mt of estimated coal). A 

further deposit north of Zabzak contains 6.55 Mt of probably coal and 3.0 Mt of possible coal. 

19A.7.3.4 Madzid-i Cobi Deposit, Kabul Province

Of 4 coal seams contains 9.5 Mt of coal reserves (4.9 Mt of proved and mineable reserves and 

4.3 Mt of probably reserves).

19A.7.3.5 The Sari-i Assia Deposit, Kunduz Province

This occurrence contains 5.84 Mt of coal (1.07 Mt of proved and mineable reserves and 4.77 Mt 

of probably reserves) (Votrubec, 1982, p. 418). 

This report focuses on the Karkar and Dudkash coal mines in the Dudkash industrial 

minerals AOI.

19A.7.4 Karkar and Dudkash Deposits and Prospects

Figure 19A–7 shows the area considered permissive for coal and the deposits described below in 

the Dudkash industrial minerals AOI (Doebrich and Wahl, 2006). 

A shepherd discovered coal at Karkar in 1938, and production began the following year. Coal 

was initially loaded into bags and taken out by donkey (Andrade, 2006). The coal mines branch of the 

Ministry of Mines was set up to develop the coal resources at Karkar and Dudkash, and at one time had 

30 regular employees at the mines, 111 officials in Kabul, 1667 contractors and 5 foreign experts from 

Czechoslovakia. It was restructured as a government enterprise in 1971 (Grantham, 2011).

In 2006–07 the four mines at Karkar, Dudkash, Ahandara and Khurdara mines and a cement 

works at Pul-e Khumri were privatized, with all movable and fixed assets transferred to the private 

Afghan Investment Company (AIC) in April 2007 (Abdullah and others, 1977; Orris, 1992). The mines 

are now operated by AIC subsidiary Afghan Coal LLC, with the intention to provide fuel for a proposed 

25 MW thermal power plant (Harben, 2002) and in limited quantities for AIC’s Ghori-I cement plant in 

Pul-e Khumri. From 1957 until 1988 the mine operated with assistance from Czechoslovakia, and used 

equipment supplied from the Warsaw Pact states. In addition, experts from India and Russia also 
1378 Summaries of Important Areas for Mineral Investment and Production Opportunities of Nonfuel Minerals in Afghanistan

provided assistance. Production peaked in the 1970s, with the Karkar mine employing 1,600 people and 

producing 600 to 700 t of coal daily. Virtually no capital investment was made in the mines after the 

Soviets left in 1989. The equipment fell into a very dilapidated state, with the mines resorting to manual 

pick-and-shovel operations. In 2004, Karkar had 318 staff, and the four mines produced around 100 t 

daily. Figure 19A–8 shows the Karkar and Dudkash mines situated side-by-side about 12 km northeast 

of Pul-e Khumri in central Baghlan province (2004) (Ministry of Mines-Islamic Republic of 

Afghanistan, 2011). Currently, the Karkar and Dudkash mines are under the management of the Afghan 

Investment Company, which has vertically integrated cement production at the Ghori Cement Works in 

Pul-e Khumri with coal production to fire the kilns and for steam turbine electrification of the cement 

plants (Erreck, 2011). 

Figure 19A–7. Permissive tract for coal occurrences. From Doebrich and Wahl (2006).
Chapter 19A. Summary for the Dudkash Industrial Minerals Area of Interest 1379

Figure 19A–8. Karkar mine entrance in Baghlan. Photograph from SanFilipo (2005).

19A.7.5 Pessimistic Factors

Although 75 percent of Afghan coal production came from the Karkar and Dudkash mines at 

some time, these mines are currently barely in production. The coal is of low quality with 10 percent ash 

content and 20.90 MJ/kg calorific value. 

Coal mining in Afghanistan is a largely unregulated affair. Total annual production in 

Afghanistan is about 200,000 t, but only about 20 percent is from government mines, mainly operated 

by the North Coal Department or associated agencies in Herat Province (SanFilipo and others, 2006). 

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