Sulfate minerals: crystallography, geochemistry, and environmental significance

615 Pages·2000·43.44 MB·English

by  C.N. Alpers

REVIEWS in
MINERALOGY &
GEOCHEMISTRY
Volume40
1955
-SULFATE MINERALS-
Crystallography, Geochemistry,
and Environmental Significance
C.N. ALPERS, J.L. JAMBOR, O.K. NORDSTROM, EDITORS
Series Editor: Paul H. Ribbe
MINERALOGICAL SOCIETY OF AMERICA
GEOCHEMICAL SOCIETY
ISSN I 529·6466
a b
Melanterite stalactite Copiapite stalagmite
(blue-green) with halotrichite (white )
c d
Voltaite Coquimbite (pale purple)
with copiapite and voltaite
I SBN 0-939950-52- 9
I I
111111111
w~ 90000
9 78 093 5 0 522 1111111111111111
- SULFATE MINERALS -

Crystallography, Geochemistry, and Environmental Significance
Reviews in Mineralogy and Geochemistry

FOREWORD
The review chapters in this volume were the basis for a short course on sulfate
minerals sponsored by the Mineralogical Society of America (MSA) November 11-12,
2000 in Tahoe City, California, prior to the Annual Meeting of MSA, the Geological
Society of America, and other associated societies in nearby Reno, Nevada. The
conveners of the course (and editors of this volume of Reviews in Mineralogy and
Geochemistry), Charles Alpers, John Jambor, and Kirk Nordstrom, also organized related
topical sessions at the GSA meeting on sulfate minerals in both hydrothermal and
low-temperature environments. A special issue of a journal yet to be identified is being
planned for the publication of research articles based on several of these presentations.
Taken together, the MSA short course and the related GSA sessions represent the most
comprehensive grouping of technical meetings ever devoted to sulfate minerals.
ERRATA (if any) may be found at the MSA website together with access to the
black-and-white and some color representations of many STRUCTURE DRAWINGS
in Chapter 1:
http://www.minsocam.org
(click on Rev Mineral Geochem entry) Paul H. Ribbe, Series Editor
Virginia Tech, Blacksburg
December 9, 2000

PREFACE

Sulfate is an abundant and ubiquitous component of Earth's lithosphere and
hydrosphere. Sulfate minerals represent an important component of our mineral
economy, the pollution problems in our air and water, the technology for alleviating
pollution, and the natural processes that affect the land we utilize. Vast quantities of
gypsum are consumed in the manufacture of wallboard, and calcium sulfates are also
used in sculpture in the forms of alabaster (gypsum) and papier-mâché (bassanite). For
centuries, Al-sulfate minerals, or "alums," have been used in the tanning and dyeing
industries, and these sulfate minerals have also been a minor source of aluminum metal.
Barite is used extensively in the petroleum industry as a weighting agent during drilling,
and celestine (also known as "celestite") is a primary source of strontium for the
ceramics, metallurgical, glass, and television face-plate industries. Jarosite is a major
waste product of the hydrometallurgical processing of zinc ores and is used in agriculture
to reduce alkalinity in soils. At many mining sites, the extraction and processing of coal
or metal-sulfide ores (largely for gold, silver, copper, lead, and zinc) produce waste
materials that generate acid-sulfate waters rich in heavy metals, commonly leading to
contamination of water and sediment. Concentrated waters associated with mine wastes
may precipitate a variety of metal-sulfate minerals upon evaporation, oxidation, or
neutralization. Some of these sulfate minerals are soluble and store metals and acidity
only temporarily, whereas others are insoluble and improve water quality by removing
metals from the water column.
1529-6466/00/0040-0000$05.00 DOI: 10.2138/rmg.2000.40.0
There is considerable scientific interest in the mineralogy and geochemistry of sulfate
minerals in both high-temperature (igneous and hydrothermal) and low-temperature
(weathering and evaporite) environments. The physical scale of processes affected by
aqueous sulfate and associated minerals spans from submicroscopic reactions at
mineral-water interfaces to global issues of oceanic cycling and mass balance, and even
to extraterrestrial applications in the exploration of other planets and their satellites. In
mineral exploration, minerals of the alunite-jarosite supergroup are recognized as key
components of the advanced argillic (acid-sulfate) hydrothermal alteration assemblage,
and supergene sulfate minerals can be useful guides to primary sulfide deposits. The role
of soluble sulfate minerals formed from acid mine drainage (and its natural equivalent,
acid rock drainage) in the storage and release of potentially toxic metals associated with
wet-dry climatic cycles (on annual or other time scales) is increasingly appreciated in
environmental studies of mineral deposits and of waste materials from mining and
mineral processing.
This volume compiles and synthesizes current information on sulfate minerals from a
variety of perspectives, including crystallography, geochemical properties, geological
environments of formation, thermodynamic stability relations, kinetics of formation and
dissolution, and environmental aspects. The first two chapters cover crystallography
(Chapter 1) and spectroscopy (Chapter 2). Environments with alkali and alkaline earth
sulfates are described in the next three chapters, on evaporites (Chapter 3).
barite-celestine deposits (Chapter 4), and the kinetics of precipitation and dissolution of
gypsum, barite, and celestine (Chapter 5). Acidic environments are the theme for the next
four chapters, which cover soluble metal salts from sulfide oxidation (Chapter 6), iron
and aluminum hydroxysulfates (Chapter 7), jarosites in hydrometallugy (Chapter 8), and
alunite-jarosite crystallography, thermodynamics, and geochronology (Chapter 9). The
next two chapters discuss thermodynamic modeling of sulfate systems from the
perspectives of predicting sulfate-mineral solubilities in waters covering a wide range in
composition and concentration (Chapter 10) and predicting interactions between sulfate
solid solutions and aqueous solutions (Chapter 11). The concluding chapter on
stable-isotope systematics (Chapter 12) discusses the utility of sulfate minerals in
understanding the geological and geochemical processes in both high-and
low-temperature environments, and in unraveling the past evolution of natural systems
through paleoclimate studies.
We thank the authors for their comprehensive and timely efforts, and for their
cooperation with our various requests regarding consistency of format and nomenclature.
Special thanks are due to the numerous scientists who provided peer reviews, which
substantially improved the content of the chapters. This volume would not have been
possible without the usual magic touch and extreme patience of Paul H. Ribbe, Series
Editor for Reviews in Mineralogy and Geochemistry. Finally, we thank our families for
their support and understanding during the past several months.
Charles N. Alpers
U.S. Geological Survey, Sacramento
John L. Jambor
Leslie Research and Consulting &
Department of Earth and Ocean Sciences,
University of British Columbia,
Vancouver
D. Kirk Nordstrom
U.S. Geological Survey, Boulder
October 6, 2000
1529-6466/00/0040-0000$05.00 DOI: 10.2138/rmg.2000.40.0
RiMG Volume 40. SULFATE MINERALS:
Crystallography, Geochemistry, and Environmental Significance
Table of Contents
n
The Crystal Chemistry of Sulfate Minerals
Frank C. Hawthorne, Sergey V. Krivovichev, Peter C. Burns
INTRODUCTION ................................................................................... 1
CHEMICAL BONDING ............................................................................ 1
STEREOCHEMISTRY OF SULFATE TETRAHEDRA IN MINERALS .................... 1
Variation in (S-0) distances .................................................................... 2
Variation in S-0 distances ...................................................................... 3
General polyhedral distortion in sulfate minerals ............................................ 3
S6+ H rn+ substitution in minerals and its influence on (S,1)-0 distances .............. 3
Hydrogen bonding in sulfate minerals ........................................................ 5
STEREOCHEMISTRY OF THIOSULFATE TETRAHEDRA ................................ 6
Variation in (S-0) distances .................................................................... 6
Variation in S-0 distances ...................................................................... 8
The formal valences of S in the thiosulfate group ............................................ 8
STEREOCHEMISTRY OF FLUOROSULFATE TETRAHEDRA ............................ 8
Variation in S-0 distances ...................................................................... 9
MOLECULAR-ORBITAL STUDIES OF S0 POLYHEDRA ................................ 10
4
The role of 3d-orbitals in bonding in sulfates ............................................... 10
Stability of the (S0 2-tetrahedron ............................................................ 10
)
4
(H S0 and (H S 0 clusters: prediction of equilibrium geometry ..................... 10
2 4) 2 2 7)
Bond angles in (S0 i-tetrahedra ............................................................. 11
4
Alkali metal-sulfate clusters ................................................................... 12
Experimental studies of electron density ..................................................... 13
Theoretical studies of electron densities ...................................................... 14
Models of chemical bonding ................................................................... 14
HIERARCHICAL ORGANIZATION OF CRYSTAL STRUCTURES ..................... 14
POLYMERIZATION OF S0 AND OTHER T0 TETRAHEDRA .......................... 16
4 4
A STRUCTURAL HIERARCHY FOR SULFATE MINERALS ............................ 17
STRUCTURES BASED ON SULFATE TETRAHEDRA AND DIY ALENT
AND/OR TRIVALENT CATION OCTAHEDRA ............................................ 17
Graphical representation of octahedral-tetrahedral structures ............................. 17
Structures with unconnected S0 groups .................................................... 18
4
Structures with finite clusters of polyhedra .................................................. 24
Structures with infinite chains ................................................................. 30
Structures with infinite sheets ................................................................. 40
Structures with infinite frameworks .......................................................... 53
STRUCTURES WITH NON-OCTAHEDRAL
CATION-COORDINATION POLYHEDRA .................................................. 61
Calcium-sulfate minerals ....................................................................... 61
Alkali-metal- and NH -sulfate minerals ...................................................... 66
4
---------
v
' y
Apatite-like structures ................................................... ~~~ ............... 80
Sulfates with the barite structure .............................................................. 80
Pb (S0 )(C0 )iOH) polymorphs ........................................................... 80
4 4 3 2
Uranyl sulfates .................................................................................. 80
Sulfates with non-sulfate tetrahedral sheets or frameworks ............................... 82
Basic sulfates of Sb3+ and B?+ ................................................................ 84
Miscellaneous sulfates .......................................................................... 89
STRUCTURES WITH ANION-CENTERED TETRAHEDRA .............................. 90
THIOSULFATE MINERALS ..................................................................... 91
SULFITE MINERALS ............................................................................. 94
FLUOROSULFATE MINERALS ................................................................ 98
ACKNOWLEDGMENTS .......................................................................... 98
APPENDIX: Index of mineral names and the table numbers in which they appear ......... 99
REFERENCES .................................................................................... 101
~ X-ray and Vibrational Spectroscopy of Sulfate
in Earth Materials
Satish C. B. Myneni
INTRODUCTION ................................................................................ 113
X-RAY SPECTROSCOPY ...................................................................... 115
X-ray absorption spectroscopy (XAS) ..................................................... 116
X-ray absorption spectroscopy at the sulfur L-edge ...................................... 137
X-ray photoelectron spectroscopy .......................................................... 139
X-ray imaging and spectrornicroscopy ..................................................... 140
VIBRATIONAL SPECTROSCOPY. ........................................................... 140
Symmetry and vibrational modes of sulfate and its complexes .......................... 143
Data collection and analysis .................................................................. 145
Vibrational spectra of sulfate in solids ...................................................... 146
Vibrational spectra of sulfate in aqueous solutions ....................................... 147
Vibrational spectra of sulfate at the interfaces ............................................. 158
Spectromicroscopy of sulfates .............................................................. 164
COMPLEMENTARY SPECTROSCOPIC METHODS ...................................... 165
Scattering methods ............................................................................ 165
Infrared emission spectroscopy ............................................................. 165
Optical spectroscopy .......................................................................... 165
SUMMARY ANDFUTUREDIRECTIONS .................................................. 166
ACKNOWLEDGMENTS ........................................................................ 166
REFERENCES .................................................................................... 167
Sulfate Minerals in Evaporite Deposits
Ronald J. Spencer
SOLUBILITY CONTROLS ON MINERAL PRECIPITATION
AND PATHS OF EVAPORATION ......................................................................... 173
Solubility of Na-K-Ca-Mg-bearing sulfate minerals ................................................ 174
Chemical divides in the system Ca2+-SO/ -HC0 175
- ...................................................
3
Precipitation sequences of Na-K-Mg-bearing sulfates ............................................. 176
- ------
Vl
Radium ......................................................................................... 222
Fluid inclusions ............................................................................... 222
BARITE IN SUBMARINE VOLCANIC HYDROTHERMAL SYSTEMS ............... 223
Sulfide-poor barite deposits of Archean age ............................................... 224
Volcanic-hosted massive sulfide (VHMS) deposits ...................................... 227
Modem submarine hydrothermal barite .................................................... 227
EXHALATIVE (SED EX) DEPOSITS OF BARITE ....................
SEDIMENTARY 228
Proterozoic barite ............................................................................. 229
Phanerozoic convergent continental margins .............................................. 230
Ordovician-Devonian Roberts Mountain allochthon, Nevada ........................... 232
Cenozoic strike-slip margins ................................................................ 237
Sedex barite deposits in active marine evaporite settings ................................. 238
The question of metal-bearing and metal-free bedded barite deposits .................. 238
CENOZOIC PELAGIC BARITE AND DISPERSED BARITE
IN DEEP SEA SEDIMENTS .................................................................. 239
Barite in seawater ............................................................................. 239
Mode(s) of precipitation of pelagic barite .................................................. 239
Fate of barite in the water column ........................................................... 241
Barite in deep-sea sediments ................................................................. 241
EPIGENETIC BARITE DEPOSITS AND EVAPORITES .................................. 245
Carbonate-hosted barite deposits ............................................................ 245
Continental rifts ............................................................................... 250
Barite in late-stage thrust belts ............................................................... 251
Dispersed cements and nodules of barite ................................................... 252
BARITE OF CONTINENTAL IGNEOUS AND
IGNEOUS-HYDROTHERMAL ORIGIN ................................................... 253
Carbonatites ................................................................................... 253
Other magmatic examples .................................................................... 254
Hydrothermal barite in the Cordilleran of the western United States ................... 254
Barite from outer space ....................................................................... 255
BEHAVIOR OF BARITE DURING WEATHERING,
DIAGENESIS, AND METAMORPHISM .................................................. 255
Formation of barite in soil environments ................................................... 255
Subaerial weathering of barite ............................................................... 255
Solution and reprecipitation of barite in diagenetic redox fronts ........................ 255
Behavior of barite during metamorphism .................................................. 256
CELESTINE IN SEDIMENTARY ENVIRONMENTS ..................................... 257
Pelagic celestine ............................................................................... 257
Carbonate sediments .......................................................................... 258
Celestine in coastal carbonate-evaporite sequences ....................................... 259
ENVIRONMENTAL ASPECTS ................................................................ 260
Barium in potable water supplies ........................................................... 260
Barite and the uranium industry ............................................................. 261
Problems related to oil and gas production ................................................ 261
_ An example of a "bad rap" for barite ....................................................... 262
CONCLUDING REMARKS .........................................................~ .... 263
ACKNOWLEDGMENTS ........................................................................ 263
REFERENCES .................................................................................... 263
viii
Evaporation paths and mineralogy of marine evaporites .......................................... 179
Evaporation paths and mineralogy of non-marine evaporites ................................... 182
MINERAL TEXTURES AND FABRICS ................................................................... 185
Criteria for syndepositional features ........................................................................ 185
Criteria for burial alteration features ........................................................................ 187
Ambiguous features ................................................................................................ 188
SUMMARY ............................................................................................................... 189
REFERENCES ........................................................................................................... 189
Barite-Celestine Geochemistry
and Environments of Formation
Jeffrey S. Hanor
INTRODUCTION ................................................................................ 193
Geological significance of barite and celestine ............................................ 193
Economic importance ......................................................................... 193
Some conventions and terms used in this chapter. ........................................ 194
PHYSICAL CHEMISTRY ...................................................................... 195
Crystal chemistry and solid-phase relations ............................................... 195
Solubility of barite and celestine in aqueous solutions ................................... 196
Stability ranges in multi component systems ............................................... 202
Ba, Sr, AND SIN CRUSTAL ROCKS AND NATURAL WATERS ..................... 205
Crustal abundance and controls on the distribution of Ba and Sr ....................... 205
Sulfate geochemistry ......................................................................... 206
Waters in sedimentary basins ................................................................ 206
Meteoric ground waters ....................................................................... 208
Seawater ....................................................................................... 208
River and estuarine waters ................................................................... 210
Waters in crystalline rocks ................................................................... 210
Continental rifts ............................................................................... 210
Seafloor hydrothermal vents ................................................................. 211
Review of controls on Sr/Ba ratios in natural waters ..................................... 211
ENVIRONMENTS OF FORMATION OF BARITE AND CELESTINE:
AN OVERVIEW ................................................................................ 211
Mechanisms for the precipitation of barite and celestine ................................. 212
Relation of barite and celestine occurrences to global tectonics
and regional hydrogeology ............................................................... 214
Relation of barite and celestine occurrences to the secular evolution
of sedimentary rock types ................................................................ 214
Marine versus continental barite ............................................................. 214
CHEMICAL AND ISOTOPIC COMPOSITION OF
BARITE AND CELESTINE: AN OVERVIEW ............................................. 215
Frequency distribution of compositions in the barite-celestine series ................... 215
B a-Sr zoning in barite-celestine ............................................................. 217
Other cations ................................................................................... 218
Strontium isotopic composition ............................................................. 218
Sulfur isotopic composition ................................................................. 220
Oxygen isotopic comQosition .. ~ ........................................................ 222
vii
Precipitation and Dissolution of Alkaline Earth Sulfates:
Kinetics and Surface Energy
A. Hina and G. H. Nancollas
INTRODUCTION ...................................................................................................... 277
DRIVING FORCES FOR GROWTH AND DlSSOLUTION ...................................... 277
Supersaturation ..................................................................................................... 277
DEFINITION AND DETERMINATION OF GROWTH RATE ................................. 278
Rate determination ................................................................................................ 279
CRYSTALLIZATION AND DISSOLUTION KINETICS .......................................... 282
Homogeneous nucleation ...................................................................................... 282
Heterogeneous nucleation ..................................................................................... 285
Determination of interfacial free energy ................................................................ 286
Interfacial energies between minerals and aqueous solutions ................................. 290
CONTACT- ANGLE METHOD ................................................................................. 292
Surface-tension component theory ......................................................................... 292
Contact-angle measurement and thin-layer wicking ............................................... 293
CONCLUSIONS ........................................................................................................ 295
NOMENCLATURE ................................................................................................... 296
Symbols ................................................................................................................ 296
Subscripts and superscripts .................................................................................... 297
REFERENCES ........................................................................................................... 297
(6
Metal-sulfate Salts from Sulfide Mineral Oxidation
John L. Jambor, D. Kirk Nordstrom, Charles N. Alpers
COMPOSITIONS AND CRYSTAL CHEMISTRY
OF HYDRATED METAL SALTS ............................................................ 305
Divalent cations ................................................................................ 305
Trivalent cations ............................................................................... 315
Mixed divalent-trivalent salts ................................................................ 317
Other minerals ................................................................................. 319
PROCESSES OF FORMATION, TRANSFORMATION AND DISSOLUTION ........ 319
Pyrite oxidation ................................................................................ 319
Field studies ................................................................................... 321
Dissolution during rainfall events ........................................................... 325
Laboratory studies ............................................................................ 327
Solubilities and stability relationships ...................................................... 327
PARAGENESIS .................................................................................. 339
ACKNOWLEDGMENTS ........................................................................ 340
REFERENCES .................................................................................... 340
ix
7/
Iron and Aluminum Hydroxysulfates from Acid Sulfate Waters
J. M. Bigham, D. Kirk Nordstrom
INTRODUCTION TO ACID SULFATE ENVIRONMENTS ..................................... 351
Mine drainage ....................................................................................................... 351
Residues from mineral extraction and ore processing ............................................ 353
Rock weathering ................................................................................................... 353
Acid sulfate soils (cat clays) .................................................................................. 354
FORMATION OF ACID SULFATE WATERS AND ASSOCIATED
WEATHERING PRODUCTS OF Fe AND Al ......................................................... 356
The Fe system ....................................................................................................... 356
The Al system ....................................................................................................... 360
Fe AND AI HYDROXYSULFATES OF LOW CRYSTALLINITY ........................... 362
Schwertmannite [Fe 0 (0H) S0 ·nH 0] ............................................................... 362
8 8 6 4 2
Hydroxysulfates of Al ........................................................................................... 369
FORMATION AND DECOMPOSITION OF Fe- AND
Al-HYDROXYSULFATES OF LOW CRYSTALLINITY ...................................... 376
Biological influences on mineral formation ........................................................... 376
GEOCHEMICAL CONTROLS ON MINERAL FORMATION ................................. 378
The Fe System ...................................................................................................... 379
The AI system ....................................................................................................... 384
ENVIRONMENTAL IMPLICATIONS OF TRACE ELEMENT SORPTION ............ 385
Sorption of metal cations ....................................................................................... 387
Sorption of oxyanions ........................................................................................... 389
Mineral instability and possible affects on sorbed species ...................................... 391
SUMMARY ............................................................................................................... 391
REFERENCES ........................................................................................................... 393
~ Jarosites and Their Application in Hydrometallurgy
John E. Dutrizac, John L. Jambor
INTRODUCTION ...................................................................................................... 405
SYNTHESIZED MEMBERS OF THE JAROSITE SUBGROUP ............................... 408
OCCURRENCES OF THE JAROSITE SUBGROUP ................................................. 408
Oxidized sulfide deposits and pyritiferous rocks .................................................... 408
Nodules and disseminations in clays ...................................................................... 411
Acid soils .............................................................................................................. 411
H . .
ypogene Jarosite ................................................................................................. 412
Alteration of minerals of the jarosite subgroup ...................................................... 412
CONDITIONS AFFECTING THE SYNTHESES
OF THE JAROSITE SUBGROUP ............................................................................ 416
Sodium, potassium, and ammoniumjarosites ........................................................ 416
JAROSITE PRECIPITATION IN THE ZINC INDUSTRY ........................................ 421
Outline of the jarosite process ............................................................................... 421
Metallurgical problems and environmental concerns ............................................. 422
KINETICS OF JAROSITE PRECIPITATION ............................................................ 423
Flow sheets ............................................................................................................ 427
X