Publications
1. D.A. Spears, 1961. Joints in the Whin Sill and associated sediments in Upper Teesdale, Northern Pennines. Proc. Yorks. Geol. Soc., 33, 21-30.
2. D.A. Spears, 1961. The distribution of alpha radioactivity in a specimen of Shap Granite. Geol. Mag., 98, 483-487.
3. D.A. Spears, 1964. The radioactivity of the Mansfield Marine Band, Yorkshire. Geochim. et Cosmochim. Acta 28, 673-681.
4. D.A. Spears, 1964. The major element geochemistry of the Mansfield Marine Band in the Westphalian of Yorkshire. Geochim. et Cosmochim. Acta, 28, 1679-1696.
5. D.A. Spears, 1965. Boron in some British Carboniferous sedimentary rocks. Geochim et Cosmochim. Acta., 29, 315-328.
6. D.A. Spears, 1965. Chemical logging of strata from boreholes. Oil and Gas Journal, August, 130-134.
7. R.M.C. Eagar & D.A. Spears, 1966. Boron content in relation to organic carbon and to palaeosalinity in certain British Upper Carboniferous sediments. Nature, London, 209, 177-181.
8. D.A. Spears, 1966. A Westphalian tonstein from South Staffordshire. Proc. Yorks. Geol. Soc. 35, 523-548.
9. R.D. Taylor & D.A. Spears, 1967. An unusual carbonate band in the East Pennine Coalfield (England). Sedimentol. 9, 55-73
10. C.D. Curtis & D.A. Spears, 1968. The formation of sedimentary iron minerals. Econ. Geol. 63, 257-270. *
11. D.A. Spears, 1969. A laminated marine shale of Carboniferous age from Yorkshire, England. Jour. Sediment. Petrol. 39, 106-112.
12. R. Till & D.A. Spears, 1969. The determination of quartz in sedimentary rocks using an X-ray diffraction method. Clays and Clay Minerals, 17, 323-327.
13. R.K. Taylor & D.A. Spears, 1970. The breakdown of British Coal Measures Rocks. Int. J. Rock. Mech. Min. Sci., 17, 481-501. *
14. D.A. Spears, 1970. A kaolinite mudstone (tonstein) in the British Coal Measures. Jour. Sed. Petrol. 40, 386-394.
15. D.A. Spears, R.K. Taylor & R. Till, 1971. A mineralogical and geochemical investigation of a spoil heap at Yorkshire Main Colliery. Q. Jl. Engng. Geol. 3, 239-252.
16. C.D. Curtis & D.A. Spears, 1971. Diagenetic developments of kaolinite. Clays and Clay Minerals, 19, 219-227.
17. D.A. Spears, 1971. The mineralogy of the Stafford Tonstein. Proc. Yorks. Geol. Soc., 38, 497-516.
18. D.A. Spears, 1971. Boron and other elements, in some Namurian Shales form the North of England. C. R. 6th Int. Carboniferous Congress, Sheffield, 1967, IV, 1481-1490.
19. D.A. Spears & R.K. Taylor, 1972. The influence of weathering on the composition and engineering properties of in-situ Coal Measures rocks. Int. J. Rock. Mech. Min. Sci., 9, 729-756. *
20. R.K. Taylor & D.A. Spears, 1972. The geotechnical characteristics of a spoil heap at Yorkshire Main Colliery. Q. Jl. Engng. Geol., 5, 243-263.
21. D.A. Spears, 1973. Relationship between exchangeable cations and palaeosalinity. Geochim. Cosmochim Acta, 37, 77-85.
22. D.A. Spears & C.M. Rice, 1973. An Upper Carboniferous tonstein of volcanic origin. Sedimentol., 20, 281-294.
23. D.A. Spears, 1974. The Rb-Sr age dating of some Carboniferous shales. Geochim. Cosmochim Acta, 38, 235-244.
24. D.A. Spears, 1974. Relationship between water-soluble cations and palaeosalinity. Geochim. Cosmochim. Acta, 38, 567-575.
25. D.A. Spears, 1975. Mineralogy and geochemistry of some Quaternary deposits in the Vale of York. Proc. Yorks. Geol. Soc. 40, 353-372.
26. D.A. Spears & M.J. Reeves, 1975. The infiltration rate into an aquifer determined from the dissolution of carbonate. Geol. Mag., 112, 585-591.
27. D.A. Spears & M.J. Reeves, 1975. The influence of superficial deposits on groundwater quality in the Vale of York. Q. Jl. Engng. Geol. 8, 255-269.
28. D.A. Spears & R. Kanaris-Sotiriou, 1975. Titanium in some Carboniferous sediments from Great Britain. Geochemica, Cosmochim Acta, 40, 345-351. *
29. D.A. Spears, 1976. The fissility of some Carboniferous shales. Sedimentology, 23, 721-725.
30. D.A. Spears, 1976. Information on groundwater composition obtained from a laboratory study of a sediment-water interaction. Q. Jl. Engng. Geol. 9, 25-36.
31. P.M. Fellows & D.A. Spears, 1978. The determination of feldspars in mudrocks using X-ray diffraction methods. Clays and Clay Minerals, 26, 231-236.
32. D.A. Spears, 1979. Porewater composition in the unsaturated zone of the Chalk, with particular reference to nitrates. Q. Jl. Engng. Geol. 12, 97-105.
33. D.A. Spears & R. Kanaris-Sotiriou, 1979. A geochemical and mineralogical investigation of some British and other European tonsteins. Sedimentology, 26, 407-425. *
34. D.A. Spears, 1979. Geochemical aspects of the Santonian Chalk of Ramsgate, England, and the origin of the chert and clay minerals. Min. Mag., 43, 159-164.
35. D.A. Spears, 1980. Towards a classification of shales. J. geol. Soc. London.137, 125-129.
36. D.A. Spears & M.A. Amin, 1981. Geochemistry and mineralogy of marine and non-marine Namurian black shales from the Tansley Borehole, Derbyshire. Sedimentology, 28, 407-417.
37. D.A. Spears, 1981. Field classification of fine-grained sedimentary rocks - Discussion. J. Sed., Pet., 51, 1031-32.
38. R.K. Taylor & D.A. Spears, 1981. Laboratory investigation of mudrocks. Q. Jl. Engng. Geol. 14, 291-309. *
39. D.A. Spears & M.A. Amin, 1981. A mineralogical and geochemical study of turbidite sandstones and interbedded shales, Mam Tor, Derbyshire. Clay Minerals, 16, 333-345.
40. D.A. Spears, 1982. The recognition of volcanic clays and the significance of heavy minerals. Clay Minerals, 17, 373-375.
41. D.A. Spears, 1983. Geochemistry and mineralogy of Triassic sandstones and implications for groundwater composition. Min. Mag., 47, 183-190.
42. D.A. Spears, 1983. Porewater reactions in the unsaturated zone with special reference to groundwater quality in England, pp. 13-18. In: ‘Residual Deposits’, R.C.L. Wilson (ed) Geol. Soc., London - Special Publication No. 11, pp. 258.
43. Bouroz, D.A. Spears & F. Arbey, 1983. Essai de synthese des donnees acquises sur la genese et l‘evolution des marqueurs petrographiques dans les bassins houillers. Memoire XVI, Soc. Geol. du Nord. pp. 114.
44. D.A. Spears & McL. D. Duff 1984. Kaolinite and mixed-layer illite/smectite in Lower Cretaceous bentonites from the Peace River Coalfield, British Columbia. Can. J. Earth Sci., 21, 465-476.
45. S.A. Caswell, I.F. Holmes & D.A. Spears, 1984. Total chlorine in coal seam profiles from the South Staffordshire (Cannock) Coalfield. J. Inst. Fuel, 63, 782-787.
46. S.A. Caswell, I.F. Holmes & D.A. Spears, 1984. Water-soluble chlorine and associated major cations from the coal and mudrocks of the Cannock and North Staffordshire coalfields. J. Inst. Fuel, 63, 774-781.
47. D.A. Spears & H.I. Sezgin, 1985. Mineralogy and geochemistry of the G. subcrenatum Marine Band and associated sediments, Langsett, South Yorkshire. J. Sedim. Petrol, 55, 570-578.
48. D.A. Spears 1985. Mineralogical control on the chemical evolution of groundwater. Chapter 5 in: Solute Processes, S.T. Trudgill, ed. John Wiley, Chichester. pp. 167-192. *
49. A. Bouroz & D.A. Spears, 1985. Influence of water depth on the alteration processes of cinerites in the sedimentary basin-importance of pedogenesis. C. R. 10th Int. Carboniferous Congress, Madrid, 1983, vol. 4, 172-176.
50. D.A. Spears & P.McL. D. Duff, 1985. Report on cinerites and tonstein symposium. In: C.R. 10th Int. Carboniferous Congress, Madrid, 1983, vol. 4, 171-173.
51. T.A. Teale & D.A. Spears, 1986. The mineralogy and origin of some Silurian bentonites, Welsh Borderland, U.K. Sedimentology, 33, 757-765.
52. D.A. Spears, 1986. Pollution investigation of a Triassic sandstone aquifer: the role of mineralogy, 211-218. Groundwater in Engineering Geology, Special Publication in Engineering Geology No. 3, Geol. Soc. London. *
53. D.A. Spears & S.A. Caswell, 1986. Mineral matter in Coals:- Cleat minerals and their origin in some coals from the English Midlands. Int. J. Coal Geology. 6. 107-125. *
54. D.A. Spears, 1987. Clay minerals and sedimentary facies in the Upper Carboniferous Pennine Basin, England. A Review. Proc. Int. Clay Conference, Denver, 1985. Eds. L.G. Schultz, H. van Olphen & F.A. Mumpton. (Clay Minerals Society, Bloomington, Indiana), 105-110.
55. D.A. Spears, 1987. An investigation of metal enrichment in Triassic sandstones and porewaters below an effluent spreading site, West Midlands, England. Quart. Jl. Engng. Geol., 20, 117-129.
56. D.A. Spears, 1987. Mineral matter in coals, with special reference to the Pennine Coalfields, 171-185, In: Scott, A.C. (ed.). Coal and coal-bearing strata: recent advances. Geological Society Special Publication, No. 32.
57. D.A. Spears, P.McL. Duff & P.M. Caine, 1988. The West Waterberg Tonstein, South Africa. Int. J. Coal Geology, 9, 221-233.
58. D.A. Spears, 1989. Aspects of iron incorporation into sediments with special reference to the Yorkshire ironstones. In: Young T. and Taylor, W.E.G. (eds), Phanerozoic Ironstones. Geological Society Special Publication, No. 46, 19-30.
59. J.H. Rippon & D.A. Spears, 1989. The sedimentology and geochemistry of the sub-Clowne cycle (Westphalian B) of northeast Derbyshire, U.K. Proc. Yorks. Geol. Soc., 47, 181-198.
60. R.N. White, J.V. Smith, D.A. Spears, M.L. Rivers & S.R. Sutton, 1989. Analysis of iron sulphides from U.K. coal by synchrotron radiation X-ray fluorescence. J. Inst. Fuel, 68, 1480-1486. *
61. W.D. Huff and D.A. Spears, 1989. A tonstein from the Lower Limestone Group of Arran. Scott. J. Geol., 25, 161-172.
62. S. Pike, M.G. Dewison & D.A. Spears, 1989. Sources of error in low temperature plasma ashing procedures for quantitative mineral analysis of coal ash. J. Inst. Fuel, 68, 664-668.
63. D.A. Spears, 1990. Kaolinite in Coal Measures sediments from the Pennine Basin, England: A review. Proceedings of the 9th International Clay Conference, Strasbourg, Sciences Geologiques, Memoires 85, 115-124.
64. D.A. Spears, 1991. Pyrite in some U.K. coals. P.R. Dugan, D.R. Quigley and Y.A. Attia (eds). Processing and utilisation of high sulfur coals VI. Coal Science and Technology, 18, 85-93.
65. M. Romano & D.A. Spears, 1991. Bentonites from the Horton Formation (Upper Silurian) of Ribblesdale, Yorkshire. Proc. Yorks. Geol. Soc., 48, 277-285.
66. M.G. Stamatakis, R. Kanaris-Sotiriou & D.A. Spears, 1991. Authigenic silica polymorphs and the geochemistry of Pliocene siliceous swamp sediments of Andea volcanic province, Greece. Canadian Mineralogist, 29, 587-598.
67. J. M. Warrender & D. A. Spears, 1991. Calcite Cemented Layers, Their Characterization and Use in Improving Reservoir Recovery from Murchison Field, Northern North Sea. AAPG Search and Discovery Article #91007© 1991 AAPG International Conference, London.
68. M.R. Martinez-Tarazona, D.A. Spears, J.M. Palacios, A. Martinez-Alonso & J.M.D. Tascon, 1992. Mineral matter in coals of different from the Asturian central basin. Fuel, 71, 367-372.
69. M.R. Martinez-Tarazona, D.A. Spears & J.M.D. Tascon, 1992. Organic affinity of trace elements in Asturian bituminous coals. Fuel, 71, 909-917.
70. D.A. Spears & M.R. Martinez-Tarazona, 1993. Geochemical and mineralogical characteristics of a power-station feed-coal, Eggborough, England. Int. J. Coal Geology, 22, 1-20. *
71. D.A. Spears, M.R. Martinez-Tarazona & J. Lee, 1994. Pyrite in UK coals: its environmental significance. Fuel, 73, 1051-1055.
72. P.C. Lyons, D.A. Spears, W.F. Outerbridge, R.D. Congdon & H.T. Evans, 1994. Euramerican tonsteins: overview, magmatic origin and depositional-tectonic implications. Palaeogeography, palaeoclimatology, palaeoecology, 106, 113-134. *
73. A.B. Garcia, J.M.G. Vega, M.R. Martinez-Tarazona & D.A. Spears, 1994. The removal of trace elements from Spanish high rank coals by selective agglomeration process. Fuel, 73, 1189-1196.
74. D.A. Spears, 1994. Geochemistry and mineralogy of some British coals. Goldschmidt Conference, Edinburgh, 1994. Min. Mag., 58A, 870-871.
75. N.J. Riley, J. Claoue-Long, A.C. Higgins, B. Owens, D.A. Spears, L. Taylor & W.J. Varker, 1994. Geochronometry and geochemistry of the European mid-Carboniferous boundary global stratotype proposal, Stonehead Beck, North Yorkshire, U.K. Annales de la Societe geologique de Belgique, 116, 275-289.
76. D.a.spears & P.J. O’Brien, 1994. Origin of British tonsteins and tectonomagmatic implications. Zbl. Geol. Palaont. Teil 1, H5/6, 491-497.
77. S. Lee & D.A.Spears, 1995. The long-term weathering of pfa and implications for groundwater composition. Quarterly Journal of Engineering Geology. 28, 1-16
78. D.A. Spears & P.C. Lyons, 1995. An update on British Tonsteins. In: European Coal Geology, M.K.G. Whateley and D.A. Spears (Eds.), Geol. Soc. Sp. Publ. 82, 137-146.
79. D.A. Spears, 1995. Minerals in coals from the Yorkshire-Nottinghamshire Coalfields: identification and quantification. In: Coal Science and Technology 24, J.A. Pajares and J.M.D. Tascon (Eds.), 8th ICCS, Coal Science, Vol. 1, 123-138, Elsevier.
80. D.J.A. McCaffrey, D.G. Richards, D.A. Spears & M. Widdowson, 1995. Assessment of the variation in mineral matter-maceral association characteristics of a suite of UK coals. In: Coal Science and Technology 24, J.A. Pajares & J.M.D. Tascon (Eds.), 8th ICCS, Coal Science, Vol. 1, 191-203, Elsevier.
81. L. Manzanares-P, E.S. Garbett, D.A. Spears, M. Widdowson & G. Richards, 1995. Ignition of coal particles. In: Coal Science and Technology 24, J.A. Pajares and J.M.D. Tascon (Eds.), 8th ICCS, Coal Science, Vol. 1, 587-602, Elsevier.
82. P.F. Cavender & D.A. Spears, 1995. Analysis of forms of sulphur within coal, and minor and trace element associations with pyrite by ICP analysis of extraction solutions. In: Coal Science and Technology 24, J.A. Pajares & J.M.D. Tascon (Eds.), 8th ICCS, Coal Science, Vol. 2, 1653-1660, Elsevier.
83. P.F. Cavender & D.A.Spears, 1995. Assessing the geological controls on the sulphur in coal seams: progress towards predictive mapping. In: Desulphurisation, Inst. Chem. Eng. Symposium Series No. 138,197-205.
84. M.R. Martinez-Tarazona & D.A. Spears, 1996. The fate of trace elements and bulk minerals in pulverised coal combustion in a power station. Fuel Processing Technology, 47, 79-92.
85. S. Lee & D.A. Spears, 1997. Natural weathering of pulverised fuel ash and porewater evolution. Applied Geochemistry, 12, 367-376.
86. D.A. Spears, J.H. Sharp, D. Thompson & B.B. Argent, 1997. Predictions of the phases present in fly ash, their composition and the influence of these factors on its utility and disposal. Proceedings of Second International Conference on Combustion and Emissions Control, 1995. Institute of Energy, London, 71-88.
87. P.F. Cavender & D.A. Spears, 1997. Sulphur distribution in a multi-bed seam. In: European Coal Geology and Technology, R.A. Gayer and J. Pesek (Eds.), Geol. Soc. Sp. Publ., 125,245-260.
88. D.A. Spears. 1997. Environmental impact of minerals in U.K. coals. In: European Coal Geology and Technology, R.A.Gayer and J.Pesek (Eds.), Geol. Soc. Sp. Publ., 125,287-295.
89. D.A. Spears. 1997. Minimisation of waste associated with the generation of electricity. In International workshop on changing consumption patterns: Waste Prevention and Minimisation. S.Lee & E.Y.Cho (Eds.), Korea Environment Institute, 175-181.
90. S. Lee & D.A. Spears.1998. Potential contamination of groundwater by pulverised fuel ash. In: Groundwater contaminants and their migration, J.Mather, D.Banks, S.Dumpleton and M.Fermor (Eds.), Geol. Soc. Sp. Publ., 128,51-61.
91. D.A. Spears & Y. Zheng. 1999. Geochemistry and origin of elements in some UK coals. International Journal of Coal Geology, 38, 161-179.*
92. D.A. Spears, R. Kanaris-Sotiriou, N. Riley & P. Krause. 1999. Namurian bentonites in the Pennine Basin, U.K. - origin and magmatic affinities. Sedimentology, 46, 385-401.
93. C.R. Ward, D.A. Spears, C.A. Booth, I. Staton & L.W. Gurba, 1999. Mineral matter and trace elements in coals of the Gunnedah Basin, New South Wales. International Journal of Coal Geology, 40, 281-3. *
94. C.A. Booth, D.A. Spears, P. Krause & A.G. Cox. 1999. The determination of low-level trace elements in coals: the use of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Fuel, 78, 1665-1670.
95. D.A. Spears, L.I. Manzanares-Papayanopoulus & C.A. Booth. 1999. The distribution and origin of trace elements in UK coal and the importance of pyrite. Fuel, 78, 1671-1677. *
96. D.A. Spears. 1999. Clay minerals in coal combustion. In Clays for our Future. Proceedings of the 11th International Clay Conference. H.Kodama, A.R.Mermut & J.K.Torrance (Eds). Ottawa, June, 1997. 103-107.
97. D.A. Spears, J.H. Rippon & P.F. Cavender, (1999), Geological controls on the sulphur distribution in British Carboniferous Coals: A review and reappraisal. International Journal of Coal Geology, 40,59-81.*
98. D.A. Spears & C.A. Booth. 1999. The determination of trace elements in British coals using energy dispersive polarised XRF and element distributions by statistical analysis.CD ROM publication of the Proceedings of the Sixteenth Annual International Pittsburgh Coal Conference
99. C.A. Booth & D.A. Spears. 1999. Laser Ablation – Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS): Novel applications for coal research. CD ROM publication of the Proceedings of the Sixteenth Annual International Pittsburgh Coal Conference.
100. Y. Zheng & D.A. Spears. 1999. Mineralogy and geochemistry of representative UK coals and trace element associations, p603-612 in Proc. 3rd European Coal Conference 1997. Eran Nakman (Ed), Izmir, Turkey.A.I.
101. A.I. Karayigit, D.A. Spears & C.A. Booth. 2000. Distribution of environmental sensitive trace elements in the Eocene Sorgun coals, Turkey. Int. Journal of Coal Geology, 42, 297-314.
102. D.A.Spears, 2000. Role of clay minerals in UK coal combustion. Applied Clay Science, 16, 87-95.
103. A.I. Karayigit, D.A.Spears & C.A.Booth. 2000. Antimony and arsenic anomalies in the coal seams from the Gokler coalfield, Turkey. Int. Journal of Coal Geology, 44, 1-17.
104. Z. Klika, L.Bartonova & D.A. Spears, 2001, Effect of boiler output on trace element partitioning during coal combustion in two fluidised-bed power stations. Fuel, 80, 907-917.
105. Quinfu Liu, D.A.Spears, Pengfei Zhang & Hongliang Xu. 2001. The origins of kaolinite-rich rocks associated with coal measures in China. Clay Minerals. 36, 389-402.
106. Quinfu Liu, D.A.Spears & Quinpu Liu, 2001. MAS NMR study of surface-modified calcined kaolin. Applied Clay Science, 19, 89-94. *
107. D.A.Spears & C.A.Booth. 2002. The composition of size-fractionated pulverised coal and the trace element associations. Fuel, 81, 683-690.
108. D.A.Spears, 2002. Trace elements in some UK coals: Quantitative distribution within the coal. CD ROM publication of the Proceedings of the Eighteenth Annual International Pittsburgh Coal Conference, Newcastle, New South Wales, Australia.
109. M. Floyd, M.A.Czerewko, J.C.Cripps & D.A.Spears. 2003. Pyrite oxidation in Lower Lias clay at concrete highway structures affected by thaumasite, Gloucestershire, UK. Cement and Concrete Composites, 25, 1015-1024.
110. D.A. Spears. 2003. Bentonites and tonsteins. p61-63. In Encylopedia of sediments and sedimentary rocks. G.V.Middleton (ed.), Kluver Academic Publishers, Dordrecht.
111. B.B. Argent, R.G.J. Edyvean, D.A. Spears & D. Thompson. 2004. Perspective of environmental pollution. Materials Science and Technology. 20, 411-430.
112. D.A.Spears. 2004. The use of laser ablation inductively coupled plasma-mass spectrometry (LA ICP-MS) for the analysis of fly ash. Fuel, 83, 1765-1770.
113. D.A.Spears & M.R. Martinez-Tarazona. 2004. Trace elements in combustion residues from a UK power station. Fuel, 83, 2265-2270. *
114. D.A.Spears & S. Lee. 2004. Geochemistry of leachates from coal ash. In Energy, Waste and the Environment: a geochemical perspective. Giere, R. and Stille, P. (eds) Geological Society, London, Special Publications, 236, 619-639. *
115. D.A.Spears. 2005. A review of chlorine and bromine in some United Kingdom coals. International Journal of Coal Geology, 64, 257-265. *
116. M.A. Lopez-Anton, M. Diaz-Somoano, D.A. Spears & M.R. Martinez-Tarazona. 2006. Arsenic and Selenium capture by fly ashes at low temperature. Environ.Sci.Technol. 40, 3947-3951.
117. D.A. Spears, 2006. Clay mineralogy of onshore UK Carboniferous mudrocks. Clay Minerals 41, 395–416. *
118. L. Bartonova, Z .Klika & D.A. Spears. 2007 Characterization of unburnt carbon from ash after bituminous coal and lignite combustion in CFBs. Fuel, 86, 455-463.
119. D.A. Spears, A.G. Borrego, A. Cox & R.M. Martinez-Tarazona. 2007. Use of laser ablation ICP-MS to determine trace element distributions in coals, with special reference to V, Ge and Al. International Journal of Coal Geology 72, 165–176. *
120. D.A.Spears & S. J. Tewalt. 2009. The geochemistry of environmentally important trace elements in UK coals, with special reference to the Parkgate coal in the Yorkshire – Nottinghamshire Coalfield, UK. International Journal of Coal Geology 80, 157–166. *
121. D.A.Spears. 2012. The origin of tonsteins, an overview, and links with seatearths, fireclays and fragmental clay rocks. International Journal of Coal Geology 94, 22–31.
122. M.A. López Antón, D.A. Spears, ,M. Díaz Somoano & M.R. Martínez Tarazona, 2013. Thallium in coal. Analysis and Environmental implications. Fuel, 105, 13-18.
123. D.A. Spears. 2013. The determination of trace element distributions in coals using sequential chemical leaching—a new approach to an old method. Fuel, 114, 31-37.
124. D.A. Spears. 2015. The geochemistry and mineralogy of high-S coals, with examples mainly from the East Pennines Coalfield in Yorkshire and Nottinghamshire, UK: an overview. Proceedings of the Yorkshire Geological Society, 60(3), 204-226. *
125. M. Antonia López-Antón, D.A. Spears, M. Díaz-Somoano, L. Diaz & M.R. Martínez-Tarazona. 2015. Enrichment of thallium in fly ashes in a Spanish circulating fluidized-bed combustion plant. Fuel, 146, 51-55.
126. S.I. Arbuzov, A.M. Mezhibor, D.A. Spears, S.S. Ilenok, M.V. Shaldybin, & E.V. Belaya. 2015. Nature of tonsteins in the Azeisk deposit of the Irkutsk Coal Basin (Siberia, Russia). International Journal of Coal Geology, 153, 99-111.
127. D.A. Spears, 2017. The Role of Seawater on the Trace Element Geochemistry of Some UK Coals and a Tribute to Goldschmidt. Minerals, 7(8).
128. D.A. Spears & S. I. Arbuzov. 2019. A geochemical and mineralogical update on two major tonsteins in the UK Carboniferous Coal Measures. International Journal of Coal Geology, 210, 103199. *
129. S.I. Arbuzov, D.A. Spears, A.V. Vergunov, S.S. Ilenok, A.M., Mezhibor, V.P. Ivanov, & N.A. Zarubina. 2019. Geochemistry, mineralogy and genesis of rare metal (Nb-Ta-Zr-Hf-Y-REE-Ga) coals of the seam XI in the south of Kuznetsk Basin, Russia. Ore Geology Reviews, 113, 103073. *
130. S.I. Arbuzov, D.A. Spears, S.S. Ilenok, I.Yu Chekryzhov, & V.P. Ivanov. 2021. Modes of occurrence of Germanium and Tungsten in the Spetsugli Germanium Orefield, Pavlovka Brown Coal, Russian far East. Ore Geology Reviews. Ore Geology Reviews, 139, 104537