Roxley Iron Clays (200 Count)

Product Information

U. Schwertmann and R. M. Cornell, Iron oxides in the laboratory:preparation and characterization, Wiley-VCH, Weinheim, New York, 2nd completely rev. and extended edn, 2000 Search PubMed . Georgia Institute of Technology (20 Dec 2012). "Clays on Mars: More plentiful than expected". Science Daily . Retrieved 22 March 2019.

A lower amount of lepidocrocite was formed in the low Fe-load samples, as direct oxidation of Fe 2+ in presence of elevated Si concentrations (high Si/Fe ratio in solution) may mainly precipitate as ferrihydrite. 73 However, only a small fraction of the sorbed Fe in the oxic samples was formed by direct oxidation of dissolved Fe 2+ for low Fe-loading samples equilibrated at pH ∼8 (between 7 and 12%, see Fig. S4 and S5 †) compared to samples equilibrated at pH ∼7 (between 60 and 65%, see Fig. S4 and S5 †). Nevertheless both low Fe-loading samples resulted in the presence of similar solid phases. The higher fraction of lepidocrocite observed in the high Fe-loading oxic samples as compared to the low Fe-loading samples may be due to the oxidation of dissolved Fe 2+ in the presence of a low Si/Fe ratio in solutions, which favors lepidocrocite formation over ferrihydrite or through the transformation of green rust into lepidocrocite. 66,73 Because only a small fraction of the sorbed Fe (up to 20%, see Fig. S4 and S5 †) was formed by direct oxidation of dissolved Fe 2+ in high Fe-loading samples, lepidocrocite was primarily formed from the transformation of Fe-phases precipitated under anoxic conditions. The chips themselves are quite expressive, delightful pieces. They have a nice heft and come in various denominations (1s, 5s, 10s, 20s, 50s, 100s, 500s, 2000s, depending on the set). The paisley pattern enveloping these chips is quite impressive with a modest, if somewhat understated, two-tone color scheme—they aren’t loud compared to what you’d find on the Vegas strip—they serve a purpose even if they are quite reserved, but they do so with a touch of class. These are, in my opinion, very good markers, and if you are set on one piece of kit to overrule any cardboard counter or money token, these are your best bet. Kerr PF (1952). "Formation and Occurrence of Clay Minerals". Clays and Clay Minerals. 1 (1): 19–32. doi: 10.1346/CCMN.1952.0010104. Rivkin AS, Volquardsen EL, Clark BE (2006). "The surface composition of Ceres: Discovery of carbonates and iron-rich clays" (PDF). Icarus. 185 (2): 563–567. doi: 10.1016/j.icarus.2006.08.022. Previous studies have also investigated the sorption of Fe 2+ to different clay minerals at various Fe-loadings. 14,30 Collectively, the literature results suggested that depending on the Fe-loading, various Fe( II)- and Fe( III)-containing solids formed. At high Fe-loadings (0.53–2 mol Fe per kg) the formed secondary phases were predominantly Fe( II)-containing phases. 19,21 At low Fe-loadings (0.002–0.08 mol Fe per kg) mainly Fe( III)-containing phases were observed. 30,67 Our current study are in agreement with these results. The formation of an LDH phase with Fe in the octahedral sheet was observed for high Fe-loading anoxic sorption samples as shown by Jones et al. 19 Contrary, in the study by Zhu et al. 21 no Fe 2+ oxidation was observed during sorption of Fe 2+ onto Syn-1 and the formation of FeAl-LDH was suggested as the main solid phase forming. However, sorption experiments in the study by Zhu et al. were performed in an atmosphere with 5% H 2 and 95% N 2. Such elevated H 2 concentration are expected to disable H + to oxidize Fe 2+ ( cf. Fig. S2 †) and to suppress the formation of green rust as the main secondary phase. In our low Fe-loading samples, over half of Fe( II) was oxidized to Fe( III), from which a large fraction was incorporated into newly formed clay minerals. This result shows that clay minerals can play an important role in the mobility of Fe 2+ under anoxic conditions. Effects of aeration of anoxic sorption samples on Fe speciation To understand the effects of O 2-exposure on the speciation of Fe in clay suspensions (Syn-1) that were anoxically equilibrated for 1 or 30 days with Fe 2+, the anoxic suspensions were exposed to ambient air for 24 hours. Aeration resulted in a further increase in percent Fe sorption (see Fig. 4a, b and Table S2 †), despite a drop in suspension pH (between 0.8 and 3.1 pH values) as a result of hydrolysis of Fe 3+ (Table S3 †). Due to the high O 2 sensitivity of Fe 2+ at near-neutral pH, rapid oxidation of adsorbed and dissolved Fe 2+, hydrolysis of Fe 3+, and precipitation of Fe( III)-(oxyhydr)oxides may occur. This results in the release of protons, explaining the observed decrease of suspension pH.K. Lagarec and D. G. Rancourt, Recoil − Mössbauer spectral analysis software for Windows., University of Ottawa, Ottawa, 1998 Search PubMed . The contributions of Fe(OH) 2, Cl-GR, and nikischerite to the LCF of EXAFS spectra of high Fe-loading anoxic samples suggest that under our experimental conditions, Fe 2+ was mainly sorbed through the formation of Fe 2+-containing layered mineral phases. Furthermore, the inclusion of a reference spectrum for aqueous Fe 2+ in the LCF did not improve the fits significantly, confirming that outer-sphere adsorption of Fe 2+ to the clay surface was not an important sorption mechanism at neutral to weakly alkaline pH. R. Dähn, A. M. Scheidegger, A. Manceau, M. L. Schlegel, B. Baeyens, M. H. Bradbury and M. Morales, Neoformation of Ni phyllosilicate upon Ni uptake on montmorillonite: A kinetics study by powder and polarized extended X-ray absorption fine structure spectroscopy, Geochim. Cosmochim. Acta, 2002, 66, 2335–2347 CrossRef .

J. W. Gruner, The composition and structure of minnesotaite, a common iron silicare in iron formations, Am. Mineral., 1944, 29, 363–372 CAS . They come in 40mm diameters and have a hefty 14 grams a piece, plus readability is superb as these have a clear and bold font used without a monetary denomination. It’s a small detail, but some folks would be annoyed if they had a money value when these chips are used as damage tokens or counters. Good on BGG for thinking more about what a board game player might want out of a poker chip. To top it off, these have a vibrant color palate. Reds flourish, blues go deep, the whites pop against the orange flair of the edge spots. These are far more expressive compared to Roxley’s offerings which could be a good thing in your eyes. I would say that I’m a fan of both Iron Clays’ dress up and BGG’s version of what a poker chip should look like. Your milage may vary, but overall these chips are more than serviceable. L. L. Baker and D. G. Strawn, Fe K-edge XAFS spectra of phyllosilicates of varying crystallinity, Phys. Chem. Miner., 2012, 39, 675–684 CrossRef CAS .I am a board game player. I am also now the self-appointed family curator of a fairly decent sized collection of games. When budget allows for new cardboard recruits, my default is to seek out a new full game. Sometimes it flexes to admit an expansion to a beloved shelf-veteran. But when I saw the Iron Clays, all rules went out of the window. They went straight onto our shared Christmas wish list! Iron Maidens G. Ona-Nguema, G. Morin, F. Juillot, G. Calas and G. E. Brown, EXAFS analysis of arsenite adsorption onto two-line ferrihydrite, hematite, goethite, and lepidocrocite, Environ. Sci. Technol., 2005, 39, 9147–9155 CrossRef CAS PubMed . Other 2:1 clay types exist such as palygorskite (also known as attapulgite) and sepiolite, clays with long water channels internal to their structure. If you’re other than a board gamer or are into board games but also dabble in the odd poker game here or there, or are an ardent participant in those circles, Iron Clays may not be for you.

Fig. 1 Percentage of Fe 2+ sorbed on Syn-1 (∼1 g L −1) as a function of pH at different CaCl 2 concentrations. Samples in DDI water had a Ca 2+ concentration of ∼0.1 mM after 1 day equilibration. Total Fe 2+ concentrations of (a) 0.05 and (b) 0.5 mM were added and equilibrated for 1 day with 1 g L −1 Syn-1. T. B. Hofstetter, R. P. Schwarzenbach and S. B. Haderlein, Reactivity of Fe(II) species associated with clay minerals, Environ. Sci. Technol., 2003, 37, 519–528 CrossRef CAS PubMed . Andrejkovičová, S.; Velosa, A.L.; Ferraz, E.; Rocha, F. (2014). "Influence of clay minerals addition on mechanical properties of air lime–metakaolin mortars". Construction and Building Materials. 65: 132–139. doi: 10.1016/j.conbuildmat.2014.04.118. L. T. Kuhn, K. Lefmann, C. R. H. Bahl, S. N. Ancona, P. A. Lindgard, C. Frandsen, D. E. Madsen and S. Morup, Neutron study of magnetic excitations in 8-nm alpha-Fe 2O 3 nanoparticles, Phys. Rev. B: Condens. Matter Mater. Phys., 2006, 74, 184406 CrossRef .

innovative. polished. replayable. beautiful. addictive.

a b c Środoń, J. (2006). "Chapter 12.2 Identification and Quantitative Analysis of Clay Minerals". Developments in Clay Science. 1: 765–787. doi: 10.1016/S1572-4352(05)01028-7. ISBN 9780080441832. Honestly, these Iron Clays really have opened my eyes. Previously resistant to investing in accessories, I am now actually looking for games with the worst cardboard counters just so that I can revel in superior counter smugness! If you are fed up with cardboard coins lowering your fun level, I highly recommend investing in Iron Clays. After all, stunning counters are for life, not just for Christmas! C. A. Gorski, M. Aeschbacher, D. Soltermann, A. Voegelin, B. Baeyens, M. Marques Fernandes, T. B. Hofstetter and M. Sander, Redox properties of structural Fe in clay minerals. 1. Electrochemical quantification of electron-donating and -accepting capacities of smectites, Environ. Sci. Technol., 2012, 46, 9360–9368 CrossRef CAS PubMed . In submerged soils and sediments, clay minerals are often exposed to anoxic waters containing ferrous iron (Fe 2+). Here, we investigated the sorption of Fe 2+ onto a synthetic montmorillonite (Syn-1) low in structural Fe (<0.05 mmol Fe per kg) under anoxic conditions and the effects of subsequent oxidation. Samples were prepared at two Fe-loadings (0.05 and 0.5 mol Fe added per kg clay) and equilibrated for 1 and 30 days under anoxic conditions (O 2< 0.1 ppm), followed by exposure to ambient air. Iron solid-phase speciation and mineral identity was analysed by 57Fe Mössbauer spectroscopy and synchrotron X-ray absorption spectroscopy (XAS). Mössbauer analyses showed that Fe( II) was partially oxidized (14–100% of total added Fe 2+) upon sorption to Syn-1 under anoxic conditions. XAS results revealed that the added Fe 2+ mainly formed precipitates (layered Fe minerals, Fe( III)-bearing clay minerals, ferrihydrite, and lepidocrocite) in different quantities depending on the Fe-loading. Exposing the suspensions to ambient air resulted in rapid and complete oxidation of sorbed Fe( II) and the formation of Fe( III)-phases (Fe( III)-bearing clay minerals, ferrihydrite, and lepidocrocite), demonstrating that the clay minerals were unable to protect ferrous Fe from oxidation, even when equilibrated 30 days under anoxic conditions prior to oxidation. Our findings clarify the role of clay minerals in the formation and stability of Fe-bearing solid phases during redox cycles in periodically anoxic environments. D. G. Rancourt and J. Y. Ping, Voigt-based methods for arbitrary-shape static hyperfine parameter distributions in mossbauer-spectroscopy, Nucl. Instrum. Methods Phys. Res., Sect. B, 1991, 58, 85–97 CrossRef .