Preface ...................................................... хііі
List of Acronyms used in this book ............................. xv
About the Author ............................................. xvii
1 Mineral Exploration ........................................ 1
1.1 Introduction ............................................... 1
1.1.1 Why Mineral Exploration? ............................ 1
1.2 Definition ................................................. 2
1.2.1 Mineral and Rock .................................... 2
1.2.2 Ore ................................................. 2
1.2.3 Ore Deposit ......................................... 7
1.2.4 Prime Commodity, Associated Commodity and Trace
Element ............................................. 7
1.2.5 Protore ............................................. 7
1.2.6 Gangue Minerals and Tailing ......................... 8
1.2.7 Deleterious Substances .............................. 8
1.3 Exploration ................................................ 8
1.3.1 Discovery Type ...................................... 8
1.3.2 Stages of Exploration ............................... 8
1.4 Mineral Policy and Act .................................... 12
1.4.1 Australia .......................................... 12
1.4.2 Canada ............................................. 13
1.4.3 Chile .............................................. 14
1.4.4 India .............................................. 15
1.4.5 Portugal ........................................... 17
1.4.6 South Africa ....................................... 18
1.4.7 Tunisia ............................................ 18
1.4.8 Royalties and Taxation ............................. 20
1.4.9 Lease Application .................................. 20
1.5 Mineral to Metal—A Full Circle ............................ 21
Further Reading ........................................... 21
2 Economic Mineral Deposits and Host Rocks .................. 23
2.1 Definition ................................................ 23
2.2 Common Economic Minerals .................................. 24
2.3 Classification of Mineral Deposits ........................ 24
2.3.1 Geographical Localization .......................... 24
2.3.2 Depth of Occurrence ................................ 28
2.3.3 Relation to Host Rocks ............................. 28
2.3.4 Structural Control ................................. 29
2.3.5 Nature of Mineralization ........................... 31
2.3.6 Morphology ......................................... 32
2.3.7 Genetic Model ...................................... 34
2.3.8 Contained Metal .................................... 36
2.4 Host Rocks ................................................ 37
2.5 Industry Specifications ................................... 37
Further Reading ........................................... 39
3 Exploration Geology ....................................... 41
3.1 Definition ................................................ 41
3.2 Regional Planning and Organization ........................ 41
3.2.1 Bureau of Mines .................................... 42
3.2.2 Geological Survey .................................. 42
3.2.3 State/Regional Department of Mines and Geology ..... 43
3.2.4 Public Sectors Undertakings ........................ 43
3.2.5 Private Sectors .................................... 44
3.2.6 Multinational Limited Companies .................... 44
3.3 Surface Guide ............................................. 44
3.3.1 Favorable Stratigraphy and Host Rocks .............. 44
3.3.2 Weathering ......................................... 44
3.3.3 Ancient Mining and Smelting ........................ 44
3.3.4 Shear .............................................. 46
3.3.5 Lineament .......................................... 47
3.4 Topographic Survey ........................................ 47
3.5 Geological Mapping ........................................ 47
3.5.1 Surface Map ........................................ 47
3.5.2 Underground Mapping ................................ 49
3.6 Stratigraphic Correlation ................................. 50
3.7 Exploration Activity ...................................... 50
3.7.1 Regional Scale ..................................... 50
3.7.2 District Scale ..................................... 51
3.7.3 Local Scale ........................................ 51
3.7.4 Exploration Components ............................. 51
3.8 Exploration of Coal and Coal Bed Methane .................. 52
Further Reading ........................................... 53
4 Exploration Geochemistry .................................. 55
4.1 Definition ................................................ 55
4.1.1 Elemental Dispersion ............................... 55
4.1.2 Pathfinder Elements ................................ 56
4.1.3 Background and Threshold Value ..................... 56
4.1.4 Orientation Survey ................................. 56
4.1.5 Regional, District and Local Scale Geochemistry .... 57
4.2 Field Procedure ........................................... 58
4.3 Analytical Methods ........................................ 58
4.3.1 Visual Colorimeter ................................. 58
4.3.2 Emission Spectrograph .............................. 58
4.3.3 Atomic Absorption Spectrometry ..................... 58
4.3.4 X-ray Fluorescence ................................. 59
4.3.5 Inductively Coupled Plasma-Atomic Emission
Spectrometry ....................................... 59
4.3.6 Instrumental Neutron Activation Analysis ........... 59
4.3.7 Scanning/Transmission Electron Microscope .......... 59
4.3.8 Electron Microprobe and Secondary Ion Mass
Spectrometers ...................................... 59
4.3.9 Choice of Analysis ................................. 60
4.4 Data Interpretation ....................................... 60
4.5 Geochemical Methods ....................................... 60
4.5.1 Pedo-geochemical ................................... 61
4.5.2 Consolidated Weathered Cover ....................... 61
4.5.3 Litho-geochemical Survey ........................... 63
4.5.4 Drift or Till Geochemical Survey ................... 64
4.5.5 Stream Sediment Survey ............................. 65
4.5.6 Hydro-geochemical Survey ........................... 65
4.5.7 Vegetation Survey .................................. 66
4.5.8 Geo-zoological Survey .............................. 67
4.5.9 Vapor Survey ....................................... 67
4.5.10 Electro-geochemical Survey ......................... 69
4.5.11 Radiogenic Isotope Geochemistry .................... 70
4.5.12 Heavy Mineral Survey ............................... 70
4.5.13 Polymetallic-Polynodule Survey ..................... 70
4.6 Review .................................................... 70
Further Reading ........................................... 71
5 Exploration Geophysics .................................... 73
5.1 Introduction .............................................. 73
5.2 Seismic Survey ............................................ 75
5.2.1 Concept ............................................ 75
5.2.2 Stress and Strain .................................. 76
5.2.3 Elastic Moduli ..................................... 76
5.2.4 Seismic Waves ...................................... 76
5.2.5 Seismic Reflection and Refraction Method ........... 77
5.3 Gravity Survey ............................................ 78
5.3.1 Concept ............................................ 78
5.3.2 Theory ............................................. 78
5.3.3 Unit of Gravity .................................... 79
5.3.4 Rock Density ....................................... 79
5.3.5 Measurement of Gravity ............................. 79
5.3.6 Gravity Reduction .................................. 80
5.3.7 Applications ....................................... 81
5.4 Magnetic Survey ........................................... 81
5.4.1 Concept ............................................ 81
5.4.2 Theory ............................................. 82
5.4.3 Earth's Magnetic Field ............................. 82
5.4.4 Rock Magnetism ..................................... 83
5.4.5 Survey Instruments ................................. 84
5.4.6 Data Reduction ..................................... 84
5.4.7 Applications ....................................... 85
5.5 Electrical Survey ......................................... 85
5.5.1 Concept ............................................ 85
5.5.2 Resistivity Method ................................. 86
5.5.3 IP Method .......................................... 87
5.5.4 SP Method .......................................... 88
5.6 EM Survey ................................................. 88
5.6.1 Definition ......................................... 88
5.6.2 Detection of EM Field .............................. 89
5.6.3 Time-Domain Electromagnetic Survey ................. 89
5.6.4 Noncontacting Conductivity Measurement ............. 90
5.6.5 Airborne EM Survey ................................. 90
5.6.6 Applications ....................................... 90
5.7 Radiometric Survey ........................................ 90
5.7.1 Concept ............................................ 90
5.7.2 Instrument ......................................... 91
5.7.3 Radiometric Dating ................................. 91
5.7.4 Applications ....................................... 91
5.8 Borehole Logging .......................................... 92
5.8.1 Principles of Well Logging ......................... 92
5.8.2 Mise-á-la-Masse .................................... 92
5.8.3 Applications ....................................... 92
5.9 Review .................................................... 93
Further Reading ........................................... 93
6 Photogeology, Remote Sensing and Geographic Information
System in Mineral Exploration ............................. 95
6.1 Introduction .............................................. 96
6.2 Photogeology .............................................. 96
6.2.1 Evolution of Camera ................................ 96
6.2.2 Classification of Aerial Photographs ............... 97
6.2.3 Parallax ........................................... 98
6.2.4 Photographic Resolution ............................ 98
6.2.5 Problems of Aerial Photograph ...................... 98
6.2.6 Photo interpretation ............................... 99
6.2.7 Application in Mineral Exploration ................. 99
6.3 Remote Sensing ............................................ 99
6.3.1 Definition and Concept ............................. 99
6.3.2 Energy Sources and Radiation ...................... 100
6.3.3 RS System ......................................... 101
6.3.4 Characteristics of Digital Images ................. 104
6.3.5 Digital Image Processing .......................... 105
6.3.6 Interpretation .................................... 105
6.3.7 RS Application in Natural Resources ............... 105
6.4 Geographic Information System ............................ 107
6.4.1 Definition ........................................ 107
6.4.2 Components of GIS ................................. 107
6.4.3 Capabilities ...................................... 108
6.4.4 Data Input ........................................ 108
6.4.5 Projection and Registration ....................... 109
6.4.6 Topology Building ................................. 110
6.4.7 Overlay Data Analysis and Modeling ................ 110
6.4.8 GIS Application in Mineral Exploration ............ 111
6.5 Global Positioning System ................................ 112
6.5.1 Space Segment ..................................... 112
6.5.2 Ground CS ......................................... 112
6.5.3 User Segment ...................................... 112
6.5.4 Signals ........................................... 113
6.5.5 Types of GPS ...................................... 113
6.5.6 Applications ...................................... 113
6.6 Software in RS-GIS ....................................... 114
6.6.1 ArcGIS ............................................ 114
6.6.2 AutoCAD ........................................... 114
6.6.3 IDRISI ............................................ 114
6.6.4 Integrated Land and Water Information System ...... 114
6.6.5 Maplnfo ........................................... 114
6.6.6 Microstation ...................................... 115
6.6.7 PAMAP ............................................. 115
6.6.8 SPANS ............................................. 115
Further Reading .......................................... 115
7 Sampling Methods ......................................... 117
7.1 Definition ............................................... 117
7.2 Sampling Equipment ....................................... 117
7.2.1 Conventional Equipment ............................ 117
7.2.2 Drilling Techniques ............................... 118
7.3 Sampling Methods ......................................... 127
7.3.1 Soil Sampling ..................................... 127
7.3.2 Pitting ........................................... 127
7.3.3 Trenching ......................................... 128
7.3.4 Stack Sampling .................................... 128
7.3.5 Alluvial Placer Sampling .......................... 129
7.3.6 Channel Sampling .................................. 129
7.3.7 Chip Sampling ..................................... 129
7.3.8 Diamond Drill Core Sampling ....................... 129
7.3.9 Sludge Sampling ................................... 130
7.3.10 RC Drill Sampling ................................. 131
7.3.11 Grab Sampling ..................................... 131
7.3.12 Muck Sampling ..................................... 131
7.3.13 Car Sampling ...................................... 131
7.3.14 Bulk Sampling ..................................... 131
7.3.15 Ocean Bed Sampling ................................ 131
7.4 Sample Reduction for Chemical
Analysis ................................................. 132
7.5 Accuracy and Due Diligence in
Sampling ................................................. 133
7.6 Quality Assurance and Quality Control .................... 134
7.7 Optimization of Samples .................................. 135
Further Reading .......................................... 135
8 Mineral Resource and Ore Reserve Estimation .............. 137
8.1 Definition ............................................... 137
8.1.1 Estimation of Resource and Reserve ................ 138
8.1.2 Mineral Resource .................................. 138
8.1.3 Ore Reserve ....................................... 138
8.1.4 Mineable Reserve .................................. 138
8.2 Estimation of Quality .................................... 139
8.2.1 Cutoff Grade ...................................... 139
8.2.2 Minimum Width ..................................... 139
8.2.3 Cutting Factors ................................... 139
8.2.4 Average Grade ..................................... 140
8.2.5 Mineable Grade .................................... 141
8.2.6 ROM Grade ......................................... 141
8.2.7 Mill Feed and Tailing Grade ....................... 141
8.3 Conventional Resource/Reserve Estimation ................. 141
8.3.1 Old Style ......................................... 141
8.3.2 Triangular ........................................ 142
8.3.3 Square and Rectangle .............................. 142
8.3.4 Polygonal ......................................... 142
8.3.5 Isograde/lsopach .................................. 142
8.3.6 Cross-Section ..................................... 143
8.3.7 Longitudinal Vertical Section ..................... 144
8.3.8 Level Plan ........................................ 144
8.3.9 Inverse Power of Distance ......................... 145
8.4 Mineral Resource and Ore Reserve Classification .......... 147
8.4.1 Conventional Classification System ................ 148
8.4.2 USGS/USBM Classification Scheme ................... 149
8.4.3 UNFC Scheme ....................................... 150
8.4.4 JORC Classification Code .......................... 151
8.4.5 Canadian Resource Classification Scheme ........... 152
8.4.6 Comparison of Reserve Classification .............. 153
8.5 Ore Monitoring System .................................... 154
8.5.1 Representation of Mine Status ..................... 154
8.5.2 Forecast, Grade Control and Monitoring System ..... 154
Further Reading .......................................... 155
9 Statistical and Geostatistical Applications in Geology ... 157
9.1 Why Geostatistics? ....................................... 157
9.2 Statistical Applications ................................. 158
9.2.1 Universe .......................................... 158
9.2.2 Population, Sample and Sampling Unit .............. 158
9.2.3 Probability Distribution .......................... 158
9.2.4 Frequency Distribution ............................ 159
9.2.5 Normal or Gaussian Distribution ................... 159
9.2.6 Minimum, Maximum, Range, Median, Mode and Mean .... 159
9.2.7 Sample Variance and Standard Deviation ............ 161
9.2.8 Probability Plot .................................. 161
9.2.9 Lognormal or Pareto Distribution .................. 162
9.2.10 Covariance ........................................ 164
9.2.11 Correlation Coefficient ........................... 165
9.2.12 Scatter Diagram ................................... 165
9.2.13 Regression ........................................ 165
9.2.14 The Null Hypothesis ............................... 166
9.2.15 The f-Test ........................................ 167
9.2.16 The F-Test ........................................ 168
9.2.17 The Chi-Square Test ............................... 168
9.2.18 Analysis of Variance .............................. 169
9.2.19 Trend Surfaces Analysis ........................... 170
9.2.20 Moving Average .................................... 171
9.3 Misclassified Tonnage .................................... 173
9.4 Geostatistical Applications .............................. 174
9.4.1 Block Variance .................................... 174
9.4.2 Semi-variogram .................................... 174
9.4.3 Estimation Variance ............................... 179
9.4.4 Kriging ........................................... 179
9.4.5 Kriging Estimation—An Example ..................... 180
9.4.6 Benefits of Geostatistics ......................... 182
Further Reading .......................................... 182
10 Exploration Modeling ..................................... 183
10.1 Definition ............................................... 183
10.2 Types of Model ........................................... 183
10.2.1 Descriptive Model ................................. 183
10.2.2 Conceptual Model .................................. 184
10.2.3 Genetic Model ..................................... 184
10.2.4 Mineral Deposit/Belt Model ........................ 184
10.2.5 Predictive Model .................................. 184
10.2.6 Statistical and Geostatistical Model .............. 185
10.2.7 Orebody Model ..................................... 185
10.2.8 Grade-Tonnage Model ............................... 186
10.2.9 Empirical Model ................................... 189
10.2.10 Exploration Model ................................ 190
10.3 Modeling: A Holistic Dynamic Approach .................... 190
10.4 Limitations ........................................ 192
Further Reading .......................................... 192
11 Elements of Mining ....................................... 193
11.1 Definition ............................................... 193
11.2 Surface Mining ........................................... 194
11.2.1 Placer Mining ..................................... 194
11.2.2 Shallow Deposits .................................. 195
11.2.3 Open-Pit Mining for Large Deposits ................ 196
11.2.4 Ocean Bed Mining .................................. 198
11.3 Underground Mining .................................. 198
11.3.1 Mine Access ....................................... 199
11.3.2 Underground Mining of Bedded Deposits ............. 204
11.3.3 Underground Hard Rock Mining ...................... 208
11.4 Mine Machinery ........................................... 213
11.4.1 Drilling .......................................... 214
11.4.2 Mucking ........................................... 216
11.4.3 Transporting ...................................... 218
11.5 Mine Explosive ........................................... 218
11.6 Rock Mechanics and Support System ........................ 218
11.7 Mine Ventilation ......................................... 220
11.8 Mine Closure ............................................. 220
11.9 Mining Software .......................................... 221
Further Reading .......................................... 222
12 Mineral Processing ....................................... 223
12.1 Definition ............................................... 223
12.2 Ore Handling ............................................. 224
12.2.1 Cleaning .......................................... 224
12.2.2 Transportation .................................... 224
12.2.3 Stockpile ......................................... 224
12.2.4 Weighing, Sampling and ln-stream Analyzer ......... 225
12.2.5 Particle Size Analysis ............................ 227
12.3 Comminution .............................................. 227
12.3.1 Crushing .......................................... 228
12.3.2 Grinding Mill ..................................... 230
12.4 Screening and Classification ............................. 231
12.4.1 Screening ......................................... 232
12.4.2 Classification .................................... 233
12.5 Concentration ............................................ 234
12.5.1 Leaching .......................................... 234
12.5.2 Ore Sorting ....................................... 235
12.5.3 Gravity Concentration ............................. 236
12.5.4 Magnetic Separation ............................... 238
12.5.5 Electrostatic Separation .......................... 239
12.5.6 Dense Medium Separation ........................... 239
12.5.7 Flotation ......................................... 239
12.5.8 Dewatering ........................................ 246
12.5.9 Tailing Management ................................ 247
12.6 Metallurgical Accounting ................................. 248
12.6.1 Plant Recovery .................................... 248
12.6.2 Ore to Concentrate Ratio .......................... 248
12.6.3 Enrichment Ratio .................................. 249
12.6.4 Metal Balancing ................................... 249
12.6.5 Milling Cost ...................................... 249
12.6.6 Concentrate Valuation ............................. 249
12.7 Ore to Concentrate and Metal ............................. 250
Further Reading .......................................... 250
13 Mineral Economics ........................................ 251
13.1 Definition ............................................... 251
13.2 Investment Philosophy .................................... 251
13.1 Stages of Investment ..................................... 252
13.4 Investment Analysis ...................................... 253
13.4.1 Undiscounted Method ............................... 253
13.4.2 Discounted Method ................................. 254
13.5 Sources of Investment Risk ............................... 255
13.6 Investment Risk and Sensitivity Analysis ................. 256
13.7 Economic Evaluation of Mineral Deposits .................. 257
13.7.1 Evaluation Process ................................ 258
13.7.2 Order of Magnitude Feasibility or Scoping
Studies ........................................... 260
13.7.3 Pre-feasibility Study ............................. 260
13.7.4 Feasibility Study ................................. 261
13.8 Case Study of Economic Evaluation ........................ 261
13.8.1 A Zinc-Lead Project ............................... 261
13.8.2 A Zinc-Lead-Copper Silver Project ................. 262
13.9 Summary .................................................. 265
Further Reading .......................................... 266
14 Environmental System Management of Mineral Resources
and Sustainable Development .............................. 267
14.1 Definition ............................................... 267
14.2 ESM in Mineral Industry .................................. 268
14.2.1 Exploration ....................................... 268
14.2.2 Mining and Beneficiation .......................... 268
14.2.3 Smelting and Refining ............................. 280
14.2.4 International Organization for Standardization .... 280
14.2.5 Benefits of ESM ................................... 281
14.3 Sustainable Development in Mining ........................ 281
14.3.1 Indicators ........................................ 282
14.3.2 Minerals and Mining as Means of Achieving
Sustainable Development ........................... 284
Further Reading .......................................... 285
15 Mineral Exploration—Case Histories ....................... 287
15.1 Definition ............................................... 288
15.2 Zawar Group, India: An Age-Old Ancient Zinc-Lead-Silver
Mining-Smelting Tradition ................................ 288
15.2.1 An Ancient Mining Tradition ....................... 288
15.2.2 Location and Discovery ............................ 288
15.2.3 Regional Setting .................................. 289
15.2.4 Host Rock ......................................... 289
15.2.5 Mineralization .................................... 289
15.2.6 Genetic Model ..................................... 289
15.2.7 Size and Grade .................................... 289
15.2.8 Salient Features of the Mine Blocks ............... 290
15.3 Broken Hill, Australia: The Largest and Richest Zinc-
Lead-Silver Deposit in the World ......................... 290
15.3.1 Location and Discovery History .................... 290
15.3.2 Regional Setting .................................. 290
15.3.3 Host Rocks ........................................ 290
15.3.4 Mineralization .................................... 292
15.3.5 Genetic Model ..................................... 292
15.3.6 Size and Grade .................................... 292
15.4 Malanjkhand: The Single Largest Porphyry Copper-
Molybdenum Orebody in India .............................. 293
15.4.1 Location and Discovery ............................ 293
15.4.2 Regional Setting .................................. 293
15.4.3 Mineralization .................................... 294
15.4.4 Genetic Models .................................... 294
15.4.5 Size and Grade .................................... 294
15.5 Sindesar-Khurd: Routine Drilling Discovered Concealed
Zn-Pb-Ag Deposit in India ................................ 294
15.5.1 Location and Discovery ............................ 294
15.5.2 Regional Setting .................................. 295
15.5.3 Host Rocks ........................................ 296
15.5.4 Mineralization .................................... 296
15.5.5 Genetic Model ..................................... 296
15.5.6 Size and Grade .................................... 296
15.5.7 Rajpura-Dariba Mine Block ......................... 296
15.5.8 Sindesar-Khurd Mine Block ......................... 297
15.5.9 Salient Features of the Leasehold Blocks .......... 299
15.6 Neves Corvo, Portugal: Discovery of Deep-Seated
Zn-Cu-Sn Deposit: A Geophysical Success .................. 299
15.6.1 Location and Discovery ............................ 299
15.6.2 Regional Setting .................................. 301
15.6.3 Exploration ....................................... 301
15.6.4 Mineralization .................................... 302
15.6.5 Genetic Model ..................................... 303
15.6.6 Size and Grade .................................... 303
15.7 Bushveld, South Africa: The Largest Platinum-Chromium
Deposits of the World .................................... 303
15.7.1 Location and Discovery ............................ 303
15.7.2 Exploration ....................................... 303
15.7.3 Regional Setting .................................. 303
15.7.4 Genetic Model ..................................... 304
15.7.5 Mineralization .................................... 305
15.7.6 Size and Grade .................................... 305
15.8 Sudbury, Canada: The Largest Nickel-Platinum-Copper
Deposits of the World .................................... 305
15.8.1 Location and Discovery ............................ 305
15.8.2 Regional Setting .................................. 306
15.8.3 Exploration ....................................... 306
15.8.4 Mineralization .................................... 307
15.8.5 Genetic Model ..................................... 308
15.8.6 Size and Grade .................................... 308
15.9 Rampura-Agucha: The Single Largest and Richest Zn-Pb-Ag
Deposit in India: Geostatistical Applications in
Mineral Exploration ...................................... 308
15.9.1 Location and Discovery ............................ 308
15.9.2 Regional Setting .................................. 309
15.9.3 Mineralization .................................... 309
15.9.4 Genetic Models .................................... 309
15.9.5 Size and Grade .................................... 309
15.9.6 Mine Operation .................................... 309
15.9.7 Geostatistical Applications in Mineral
Exploration ....................................... 309
15.9.8 Exploration Scheme ................................ 310
15.9.9 Database .......................................... 310
15.9.10 QC and QA ........................................ 310
15.9.11 General Statistical Applications ................. 310
15.9.12 Isograde Maps .................................... 311
15.9.13 Semi-variogram ................................... 312
15.9.14 Sequential Evaluation Model ...................... 312
15.9.15 Estimation Variance and Optimization of Drill
Hole Spacing ..................................... 314
5.10 Jhamarkotra, India: Discovery of the Largest
Stromatolitic Rock-Phosphate Deposit by Geological
Modeling and Exploration to Environment Management
Practices: A Holistic Approach ........................... 315
15.10.1 Location and Discovery ........................... 316
15.10.2 Regional Settings ................................ 317
15.10.3 Host Rocks ....................................... 317
15.10.4 Mineralization ................................... 317
15.10.5 Genetic Model .................................... 317
15.10.6 Exploration ...................................... 317
15.10.7 Size and Grade ................................... 317
15.10.8 Mining ........................................... 317
15.10.9 Beneficiation .................................... 317
15.10.10 Environment Management .......................... 317
15.11 Base Metal Discovery Trend: The Last 50 Years in India .. 318
15.11.1 Significance of Investment Framework ............. 319
15.11.2 Reserve/Resources ................................ 319
15.11.3 Reserve Adequacy ................................. 320
15.11.4 Resource Requirement ............................. 320
15.11.5 Discovery Trend .................................. 320
15.11.6 A New Beginning .................................. 321
15.11.7 Conclusions ...................................... 322
Further Reading .......................................... 322
Refences ...................................................... 323
Index ......................................................... 325
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