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Literature review – Environmental impact and bioremediation of seleniferous soils and sediments
Published in Shrutika Laxmikant Wadgaonkar, Novel bioremediation processes for treatment of seleniferous soils and sediment, 2018
In soil, selenium is present in both inorganic and organic forms (Goh and Lim, 2004). About 50 minerals are formed by the combination of selenium with metals in soil (Kabata-pendias et al., 2001). Commonly found inorganic forms of selenium in soil are klockmannite (CuSe), ferroselite (FeSe2), clausthalite (PbSe), naumannite (Ag2Se) and tiemannite (HgSe) (Figure 2.3). The majority of organic forms of selenium present in soil are analogues of sulfur compounds (Kabata-pendias et al., 2001). The major geochemical characteristic exhibited by selenium is its chalcophilic tendency. The element occurs most commonly along with sulfur in volcanic regions and readily forms lattices with sulfides (Kabata-pendias et al., 2001). Because of structural similarity between Se2− and S2− anions, selenium readily substitutes sulfur in the crystal structures of many sulfide minerals (Butterman et al., 2004).
Red-bed gold deposit in the Fore-Sudetic Monocline, SW Poland: some facts and questions
Published in Adam Piestrzyński, Mineral Deposits at the Beginning of the 21st Century, 2001
The gold mineralisation occurs in both the Kupferschiefer (red-coloured section and transition zone), and the Weissliegende sandstone (reddened sections). There are three types of gold (Piestrzyński et al. 1997, Pieczonka & Piestrzyński 2000): native gold, associated with hematite and covellite, containing gold of high purity ranging between 92 and 96 wt.%electrum, associated with chalcocite, digenite, and bornite, and minor clausthalite, galena, tetraauricupride, mercurian-bearing electrum, spionkopite, yarrowite, and tiemanniteinvisible gold, dispersed in coarse-grained hematite and copper sulphides.
Se, 34]
Published in Alina Kabata-Pendias, Barbara Szteke, Trace Elements in Abiotic and Biotic Environments, 2015
Alina Kabata-Pendias, Barbara Szteke
Approximately 50 Se minerals are known, of which the relatively common are klockmanite (CuSe), berzelianite (Cu2−xSe), clausthalite (PbSe), tiemannite (HgSe), ferroselenite (FeSe2), crookesite [(Cu,Tl,Ag)2Se], and cobaltomenite [Co(SeO3) 2H2O]. Commonly Se occurs in association with some host minerals, such as pyrite, chalcopyrite, and sphalerite.
Abstracts from the 2017–2018 Mineral Deposits Studies Group meeting
Published in Applied Earth Science, 2018
L. Santoro, St. Tshipeng Yav, E. Pirard, A. Kaniki, G. Arfè, N. Mondillo, M. Boni, M. Joachimski, G. Balassone, A. Mormone, A. Cauceglia, N. Mondillo, G. Balassone, M. Boni, W. Robb, T. L. Smith, David Currie, Finlay Stuart, John Faithfull, Adrian Boyce, N. Mondillo, C. Chelle-Michou, M. Boni, S. Cretella, G. Scognamiglio, M. Tarallo, G. Arfè, F. Putzolu, M. Boni, N. Mondillo, F. Pirajno, N. Mondillo, C. Chelle-Michou, M. Boni, S. Cretella, G. Scognamiglio, M. Tarallo, G. Arfè, Saltanat Aitbaeva, Marina Mizernaya, Boris Dyachkov, Andrew J Martin, Iain McDonald, Christopher J MacLeod, Katie McFall, Hazel M Prichard, Gawen R T Jenkin, B. Kennedy, I. McDonald, D. Tanner, L. Longridge, A. M. Borst, A. A. Finch, H. Friis, N. J. Horsburgh, P. N. Gamaletsos, J. Goettlicher, R. Steininger, K. Geraki, Jonathan Cloutier, Stephen J. Piercey, Connor Allen, Craig Storey, James Darling, Stephanie Lasalle, A. Dobrzanski, L. Kirstein, R. Walcott, I. Butler, B. Ngwenya, Andrew Dobrzanski, Simon Howard, Lore Troalen, Peter Davidson, Rachel Walcott, Drew Drummond, Jonathan Cloutier, Drew Drummond, Adrian Boyce, Robert Blakeman, John Ashton, Eva Marquis, Kathryn Goodenough, Guillaume Estrade, Martin Smith, E. Zygouri, S. P. Kilias, T. Zack, I. Pitcairn, E. Chi Fru, P. Nomikou, A. Argyraki, M. Ivarsson, Adrian A. Finch, Anouk M. Borst, William Hutchison, Nicola J. Horsburgh, Tom Andersen, Siri Simonsen, Hamidullah Waizy, Norman Moles, Martin Smith, Steven P. Hollis, Julian F. Menuge, Aileen L. Doran, Paul Dennis, Brett Davidheiser-Kroll, Alina Marca, Jamie Wilkinson, Adrian Boyce, John Güven, Steven P. Hollis, Julian F. Menuge, Aileen L. Doran, Stephen J. Piercey, Mark R. Cooper, J. Stephen Daly, Oakley Turner, Brian McConnell, Hannah S. R. Hughes, Hannah S. R. Hughes, Magdalena M. Matusiak-Małek, Iain McDonald, Ben Williamson, James Williams, Guy Dishaw, Harri Rees, Roger Key, Simon Bate, Andy Moore, Katie McFall, Iain McDonald, Dominque Tanner, Manuel Keith, Karsten M. Haase, Daniel J. Smith, Reiner Klemd, Ulrich Schwarz-Schampera, Wolfgang Bach, Sam J Walding, Gawen RT Jenkin, Daniel James, David Clark, Lisa Hart-Madigan, Robin Armstrong, Jamie Wilkinson, Gawen RT Jenkin, Hugh Graham, Daniel J Smith, Andrew P Abbott, David A Holwell, Eva Zygouri, Robert C Harris, Christopher J Stanley, Hannah L.J. Grant, Mark D. Hannington, Sven Petersen, Matthias Frische, Fei Zhang, Ben J. Williamson, Hannah Hughes, Joshua Smiles, Manuel Keith, Daniel J. Smith, Chetan Nathwani, Robert Sievwright, Jamie Wilkinson, Matthew Loader, Daryl E. Blanks, David A. Holwell, W.D. Smith, J.R. Darling, D.S. Bullen, R.C. Scrivener, Aileen L. Doran, Steven P. Hollis, Julian F. Menuge, John Güven, Adrian J. Boyce, Oakley Turner, Sam Broom-Fendley, Aoife E Brady, Karen Hudson-Edwards, Oakley Turner, Steve Hollis, Sean McClenaghan, Aileen Doran, John Güven, Emily K. Fallon, Richard Brooker, Thomas Scott
SEM-EDS analysis of 26 slides characterised 849 platinum-group minerals (PGMs), with a total area of 25630 µm2. 28% of PGMs studied are present in Unit 2 and 72% are in the gabbronorite veins which intrude Unit 1. 85% of the PGMs are Pd-Bi-Te minerals, with 13% Pd-Te minerals, 1% Pt-As minerals and rare Pd-As and Pt-Te minerals. The deposit contains significant amounts of Au-rich electrum (average 83 wt.% Au), hessite, altaite and galena-clausthalite. 90% of PGMs are hosted within quartz, chlorite and talc-carbonate alteration products, with only 9% hosted within or on the edge of sulphides and 1% within silicates.
The complexity of mudstone diagenesis – some insight from the Tøyen Shale, Lower to Middle Ordovician, southern Sweden
Published in GFF, 2019
Sven O. Egenhoff, Neil S. Fishman, Heather A. Lowers, Per Ahlberg
Two types of framboid concretions have been observed in the Tøyen Shale: the first type of framboid concretion (herein referred to as framboid concretion I) is up to 750 μm × 200 μm in size, whereas the second type (framboid concretion II) is as much as 1 mm × 0.5 mm (Fig. 6B) in size. Bedding is distorted around both types of framboid concretions. The individual framboids within both of these concretions are larger (6–26 μm) than matrix framboids. The two types of concretions are further differentiated by micrometer-thick pyrite overgrowths on individual crystallites only in framboid concretion II, and which also covers entire framboids, and in places entire framboid concretions. Overgrowths can fill all micrometer-scale voids within the framboids of framboid concretion II, leading to their massive appearance in which the individual framboids are only barely recognizable (Fig. 6C). The orientation of the two types of concretions also differs: whereas framboid concretions I are elongate typically parallel to bedding, framboid concretions II are commonly elongate at an angle or roughly perpendicular to bedding. Marcasite occurs locally as bladed crystals up to 1.5 mm in length and overlying pyrite overgrowths (Fig. 7A). This occurrence of indicates that the marcasite occurs in concretionary masses (Fig. 7A). The outer rim of some marcasite blades is in turn commonly coated by euhedral pyrite (Fig. 7B). Sphalerite occurs commonly as platy to roundish crystal that are tens of micrometers in length, arranged tangentially around marcasite concretions (Fig. 6D) Further, sphalerite also fills fractures and is seemingly intergrown with single crystals of galena. EDS data shows that the galena contains selenium and is therefore mineralogically close to clausthalite (PbSe; e.g., Hower & Robertson 2003).