Corrensite and Swelling Chlorite
TL;DR: In this article, a I :I regular interstratification of chlorite and swelling chlorite is described. But it is suggested that the name corrensite be retained for the original material so described.
Abstract: Some minerals which have been referred to as corrensite are considered together with some related minerals. It is suggested that the name corrensite be retained for the original material so described namely, a I :I regular interstratification of chlorite and swelling chlorite. The possible constitution of swelling chlorite, its difference from vermiculite, and its relationship to labile chlorites produced synthetically are all discussed.
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01 Jan 1980
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01 Jan 1975
TL;DR: In this article, it was verified that this irregularity was due to the interstratification of different types of crystalline layers, which is a phenomenon that was first observed on studying clay minerals by X-ray diffraction.
Abstract: Interstratification is a phenomenon that was first observed on studying clay minerals by X-ray diffraction. It was noted that the majority of them had basal reflections (001), which did not form a regular series. It was verified that this irregularity was due to the interstratification of different types of crystalline layers.
184 citations
TL;DR: The structure and properties of sepiolite are reviewed in this paper, where surface properties, such as porosity and sorption are detailed, as well as dehydration and thermal behaviour, with appropriate pretreatments, are shown to be useful in following applications: Absorbents, environmental deodorants, catalyst carriers, polyesters, asphalt coatings; paints, pharmaceutical uses, decolorizing agents, filter aids, anticaking agents, phytosanitary carriers, cigarette filters, plastisols, rubber, animal nutrition, detergents, cosmetics, agriculture (so
Abstract: The structure and properties of sepiolite are reviewed. Surface properties, such as porosity and sorption are detailed, as well as dehydration and thermal behaviour. Industrial applications of sepiolite are based on: a) Sor-btive properties; b) rheological properties; c) catalytic properties; The Theological behaviour of sepiolite suspensions, as expressed by viscosity, is shown to be related to following factors; type of medium (aqueous or organic), type and concentration of electrolyte, pH, shear-stress and pregelification. With appropriate pretreatments, sepiolite is shown to be useful in following applications: Absorbents, environmental deodorants, catalyst carriers, polyesters, asphalt coatings; paints, pharmaceutical uses, decolorizing agents, filter aids, anticaking agents, phytosanitary carriers, cigarette filters, plastisols, rubber, animal nutrition, detergents, cosmetics, agriculture (soil conditioning, fluid carriers for pregerminated seeds, seed coating; fertilizer suspensions) grease thickeners, NCR paper, drilling fluids.
146 citations
TL;DR: In this paper, the parageneses of phyllosilicates were studied using transmission and analytical electron microscopy using DSDP Hole 504B, Leg 83, and the approach to textural equilibrium was controlled largely by the availability of fluid or permeability.
Abstract: Phyllosilicates occurring as replacements of olivine, clinopyroxene and interstitial materials and as veins or fracture-fillings in hydrothermally altered basalts from DSDP Hole 504B, Leg 83 have been studied using transmission and analytical electron microscopy. The parageneses of phyllosilicates generally change systematically with depth and with the degree of alteration, which in turn is related to permeability of basalts. Saponite and some mixed-layer chlorite/smectite are the dominant phyllosilicates at the top of the transition zone. Chlorite, corrensite, and mixed-layer chlorite/corrensite occur mainly in the lower transition zone and upper levels of the sheeted dike zone. Chlorite, talc, and mixed-layer talc/chlorite are the major phyllosilicates in the sheeted dike zone, although replacement of talc or ohvine by saponite is observed. The phyllosilicates consist of parallel or subparallel discrete packets of coherent layers with packet thicknesses generally ranging from< 100 A to a few hundred A. The packets of saponite layers are much smaller or less well defined than those of chlorite, corrensite and talc, indicating poorer crystal-linity of saponite. by contrast, chlorite and talc from the lower transition zone and the sheeted dike zone occur in packets up to thousands of A thick. The Si/(Si+Al) ratio of these trioctahedral phyllosilicates increases and Fe/(Fe+Mg) decreases in the order chlorite, corrensite, saponite, and talc. These relations reflect optimal solid solution consistent with minimum misfit of articulated octahedral and tetrahedral sheets. Variations in composition of hydrothermal fluids and precursor minerals, especially in Si/(Si+Al) and Fe/(Fe+Mg) ratios, are thus important factors in controlling the parageneses of phyllosilicates. The phyllosilicates are generally well crystallized discrete phases, rather than mixed-layered phases, where they have been affected by relatively high fluid/rock ratios as in high-permeability basalts, in veins, or areas adjacent to veins. Intense alteration in basalts with high permeability (indicating high fluid/rock ratios) is characterized by pervasive albitization and zeolitization. Minimal alteration in the basalts without significant albitization and zeolitization is characterized by the occurrence of saponite±mixed-layer chlorite/smectite in the low-temperature alteration zone, and mixed-layer chlorite/corrensite or mixed-layer talc/chlorite in the high-temperature alteration zone. Textural non-equilibrium for phyllosilicates is represented by mixed layering and poorly defined packets of partially incoherent layers. The approach to textural equilibrium was controlled largely by the availability of fluid or permeability.
107 citations
TL;DR: The current definition of corrensite as a regular 1:1 interstratification of trioctahedral chlorite and vermiculite is based on the analysis of chemical data from the literature.
Abstract: Statistical analyses of chemical data from the literature of corrensite minerals suggest a large compositional variability, more evident in octahedral than in tetrahedral coordination. Mg occupies 40–80% of the octahedral sites, with Al and Fe2+ making up the remainder. Approximately 15–30% of the tetrahedral sites are filled by Al. Despite this compositional variability, distinct fields for the several types of mixed-layer trioctahedral chlorite/trioctahedral swelling layer are not apparent. Statistical analyses of the composition of corrensite compared with saponite, vermiculite, and chlorite suggest that corrensite is an intermediate between trioctahedral chlorite and trioctahedral smectite. If Fe/(Fe + Mg) > 50%, chlorite alone is favored, but with increasing Mg, chlorite appears to transform into corrensite and then, by iron oxidation, into trioctahedral smectite. Despite the chemical variability between corrensite, chlorite, and saponite, corrensite appears chemically to be a well-defined species. On the other hand, corrensite cannot be characterized chemically on the basis of its swelling component. Thus, the current definition of corrensite as a regular 1:1 interstratification of trioctahedral chlorite and either trioctahedral smectite or vermiculite is appropriate.
50 citations
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TL;DR: Mortland as mentioned in this paper describes the progress in clay mineral studies in Japan and provides a fine contribution by including numerous chemical, differential thermal, and X-ray diffraction data on various clay mineral species.
Abstract: A comprehensiv e description of the progres in clay mineral studies in Japan is contained in this book. The author has made a fine contribution by including numerous chemical , differential thermal , and X-ray diffraction data on various clay mineral species , thus providing reference material for investigator s everywhere. The clay mineral s discusse d are primarily from geologi c deposit s with relatively littl e reference to the clay mineral s in soils. Changes taking place in clay mineral s also are discusse d largely from the viewpoint of alteration in geologic deposit s rather than during weathering in soils. In general , the criteria used for clay mineral identification are similar to those used elsewhere . An exception might be taken in the case of the criteria for vermiculite mineral s where the author reports no change in the basal spacing after heating to 100° C. for several hours and a strong 14.3 A. reflection still being maintained after heating at 300° C. At 500° C., the 14.3 A. was only partially replaced by a 9.3 A. reflection. To the reviewer, these reactions are not typical of pure vermiculite which shoul d collapse to near 10 A. upon heating to only 100° C. The reactions described by the author more nearl y fi t a vermiculite mineral which is partially chloritized, that is containing "islands" of brucite or gibbsite in the interlayer spaces , thus interfering with the complet e collapse of the vermiculite structure. In several places, the author has used the term "cation exchange" where what is meant is "isomorphous substitution. " The readabilit y of the book is marred by many instances of poor sentenc e structure and grammatical errors. Misspellings are common-place . Actual errors in data have also crept in, an exampl e of which is indicated by the reference to the exchange capacit y of a Scottich soil as being about 9 me./per g. The book would have benefited greatl y from much more thorough proofreading. Despite these faults, the data reported on various clay mineral species and interstratified systems make this book a very valuabl e reference for the scientist working with clay minerals.—M. M. MORTLAND, Michigan State University.
21 citations